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  • python的基本数据类型

    1、数字

    Python 支持三种不同的数值类型:

    • 整型(Int) - 通常被称为是整型或整数,是正或负整数,不带小数点。Python3 整型是没有限制大小的,可以当作 Long 类型使用,所以 Python3 没有 Python2 的 Long 类型。
    • 浮点型(float) - 浮点型由整数部分与小数部分组成,浮点型也可以使用科学计数法表示(2.5e2 = 2.5 x 102 = 250)
    • 复数( (complex)) - 复数由实数部分和虚数部分构成,可以用a + bj,或者complex(a,b)表示, 复数的实部a和虚部b都是浮点型。
    Help on class int in module builtins:
    
    class int(object)
     |  int([x]) -> integer
     |  int(x, base=10) -> integer
     |  
     |  Convert a number or string to an integer, or return 0 if no arguments
     |  are given.  If x is a number, return x.__int__().  For floating point
     |  numbers, this truncates towards zero.
     |  
     |  If x is not a number or if base is given, then x must be a string,
     |  bytes, or bytearray instance representing an integer literal in the
     |  given base.  The literal can be preceded by '+' or '-' and be surrounded
     |  by whitespace.  The base defaults to 10.  Valid bases are 0 and 2-36.
     |  Base 0 means to interpret the base from the string as an integer literal.
     |  >>> int('0b100', base=0)
     |  4
     |  
     |  Methods defined here:
     |  
     |  __abs__(self, /)
     |      abs(self)
     |  
     |  __add__(self, value, /)
     |      Return self+value.
     |  
     |  __and__(self, value, /)
     |      Return self&value.
     |  
     |  __bool__(self, /)
     |      self != 0
     |  
     |  __ceil__(...)
     |      Ceiling of an Integral returns itself.
     |  
     |  __divmod__(self, value, /)
     |      Return divmod(self, value).
     |  
     |  __eq__(self, value, /)
     |      Return self==value.
     |  
     |  __float__(self, /)
     |      float(self)
     |  
     |  __floor__(...)
     |      Flooring an Integral returns itself.
     |  
     |  __floordiv__(self, value, /)
     |      Return self//value.
     |  
     |  __format__(self, format_spec, /)
     |      Default object formatter.
     |  
     |  __ge__(self, value, /)
     |      Return self>=value.
     |  
     |  __getattribute__(self, name, /)
     |      Return getattr(self, name).
     |  
     |  __getnewargs__(self, /)
     |  
     |  __gt__(self, value, /)
     |      Return self>value.
     |  
     |  __hash__(self, /)
     |      Return hash(self).
     |  
     |  __index__(self, /)
     |      Return self converted to an integer, if self is suitable for use as an index into a list.
     |  
     |  __int__(self, /)
     |      int(self)
     |  
     |  __invert__(self, /)
     |      ~self
     |  
     |  __le__(self, value, /)
     |      Return self<=value.
     |  
     |  __lshift__(self, value, /)
     |      Return self<<value.
     |  
     |  __lt__(self, value, /)
     |      Return self<value.
     |  
     |  __mod__(self, value, /)
     |      Return self%value.
     |  
     |  __mul__(self, value, /)
     |      Return self*value.
     |  
     |  __ne__(self, value, /)
     |      Return self!=value.
     |  
     |  __neg__(self, /)
     |      -self
     |  
     |  __or__(self, value, /)
     |      Return self|value.
     |  
     |  __pos__(self, /)
     |      +self
     |  
     |  __pow__(self, value, mod=None, /)
     |      Return pow(self, value, mod).
     |  
     |  __radd__(self, value, /)
     |      Return value+self.
     |  
     |  __rand__(self, value, /)
     |      Return value&self.
     |  
     |  __rdivmod__(self, value, /)
     |      Return divmod(value, self).
     |  
     |  __repr__(self, /)
     |      Return repr(self).
     |  
     |  __rfloordiv__(self, value, /)
     |      Return value//self.
     |  
     |  __rlshift__(self, value, /)
     |      Return value<<self.
     |  
     |  __rmod__(self, value, /)
     |      Return value%self.
     |  
     |  __rmul__(self, value, /)
     |      Return value*self.
     |  
     |  __ror__(self, value, /)
     |      Return value|self.
     |  
     |  __round__(...)
     |      Rounding an Integral returns itself.
     |      Rounding with an ndigits argument also returns an integer.
     |  
     |  __rpow__(self, value, mod=None, /)
     |      Return pow(value, self, mod).
     |  
     |  __rrshift__(self, value, /)
     |      Return value>>self.
     |  
     |  __rshift__(self, value, /)
     |      Return self>>value.
     |  
     |  __rsub__(self, value, /)
     |      Return value-self.
     |  
     |  __rtruediv__(self, value, /)
     |      Return value/self.
     |  
     |  __rxor__(self, value, /)
     |      Return value^self.
     |  
     |  __sizeof__(self, /)
     |      Returns size in memory, in bytes.
     |  
     |  __str__(self, /)
     |      Return str(self).
     |  
     |  __sub__(self, value, /)
     |      Return self-value.
     |  
     |  __truediv__(self, value, /)
     |      Return self/value.
     |  
     |  __trunc__(...)
     |      Truncating an Integral returns itself.
     |  
     |  __xor__(self, value, /)
     |      Return self^value.
     |  
     |  bit_length(self, /)
     |      Number of bits necessary to represent self in binary.
     |      
     |      >>> bin(37)
     |      '0b100101'
     |      >>> (37).bit_length()
     |      6
     |  
     |  conjugate(...)
     |      Returns self, the complex conjugate of any int.
     |  
     |  to_bytes(self, /, length, byteorder, *, signed=False)
     |      Return an array of bytes representing an integer.
     |      
     |      length
     |        Length of bytes object to use.  An OverflowError is raised if the
     |        integer is not representable with the given number of bytes.
     |      byteorder
     |        The byte order used to represent the integer.  If byteorder is 'big',
     |        the most significant byte is at the beginning of the byte array.  If
     |        byteorder is 'little', the most significant byte is at the end of the
     |        byte array.  To request the native byte order of the host system, use
     |        `sys.byteorder' as the byte order value.
     |      signed
     |        Determines whether two's complement is used to represent the integer.
     |        If signed is False and a negative integer is given, an OverflowError
     |        is raised.
     |  
     |  ----------------------------------------------------------------------
     |  Class methods defined here:
     |  
     |  from_bytes(bytes, byteorder, *, signed=False) from builtins.type
     |      Return the integer represented by the given array of bytes.
     |      
     |      bytes
     |        Holds the array of bytes to convert.  The argument must either
     |        support the buffer protocol or be an iterable object producing bytes.
     |        Bytes and bytearray are examples of built-in objects that support the
     |        buffer protocol.
     |      byteorder
     |        The byte order used to represent the integer.  If byteorder is 'big',
     |        the most significant byte is at the beginning of the byte array.  If
     |        byteorder is 'little', the most significant byte is at the end of the
     |        byte array.  To request the native byte order of the host system, use
     |        `sys.byteorder' as the byte order value.
     |      signed
     |        Indicates whether two's complement is used to represent the integer.
     |  
     |  ----------------------------------------------------------------------
     |  Static methods defined here:
     |  
     |  __new__(*args, **kwargs) from builtins.type
     |      Create and return a new object.  See help(type) for accurate signature.
     |  
     |  ----------------------------------------------------------------------
     |  Data descriptors defined here:
     |  
     |  denominator
     |      the denominator of a rational number in lowest terms
     |  
     |  imag
     |      the imaginary part of a complex number
     |  
     |  numerator
     |      the numerator of a rational number in lowest terms
     |  
     |  real
     |      the real part of a complex number
    View Code
    Help on class float in module builtins:
    
    class float(object)
     |  float(x=0, /)
     |  
     |  Convert a string or number to a floating point number, if possible.
     |  
     |  Methods defined here:
     |  
     |  __abs__(self, /)
     |      abs(self)
     |  
     |  __add__(self, value, /)
     |      Return self+value.
     |  
     |  __bool__(self, /)
     |      self != 0
     |  
     |  __divmod__(self, value, /)
     |      Return divmod(self, value).
     |  
     |  __eq__(self, value, /)
     |      Return self==value.
     |  
     |  __float__(self, /)
     |      float(self)
     |  
     |  __floordiv__(self, value, /)
     |      Return self//value.
     |  
     |  __format__(self, format_spec, /)
     |      Formats the float according to format_spec.
     |  
     |  __ge__(self, value, /)
     |      Return self>=value.
     |  
     |  __getattribute__(self, name, /)
     |      Return getattr(self, name).
     |  
     |  __getnewargs__(self, /)
     |  
     |  __gt__(self, value, /)
     |      Return self>value.
     |  
     |  __hash__(self, /)
     |      Return hash(self).
     |  
     |  __int__(self, /)
     |      int(self)
     |  
     |  __le__(self, value, /)
     |      Return self<=value.
     |  
     |  __lt__(self, value, /)
     |      Return self<value.
     |  
     |  __mod__(self, value, /)
     |      Return self%value.
     |  
     |  __mul__(self, value, /)
     |      Return self*value.
     |  
     |  __ne__(self, value, /)
     |      Return self!=value.
     |  
     |  __neg__(self, /)
     |      -self
     |  
     |  __pos__(self, /)
     |      +self
     |  
     |  __pow__(self, value, mod=None, /)
     |      Return pow(self, value, mod).
     |  
     |  __radd__(self, value, /)
     |      Return value+self.
     |  
     |  __rdivmod__(self, value, /)
     |      Return divmod(value, self).
     |  
     |  __repr__(self, /)
     |      Return repr(self).
     |  
     |  __rfloordiv__(self, value, /)
     |      Return value//self.
     |  
     |  __rmod__(self, value, /)
     |      Return value%self.
     |  
     |  __rmul__(self, value, /)
     |      Return value*self.
     |  
     |  __round__(self, ndigits=None, /)
     |      Return the Integral closest to x, rounding half toward even.
     |      
     |      When an argument is passed, work like built-in round(x, ndigits).
     |  
     |  __rpow__(self, value, mod=None, /)
     |      Return pow(value, self, mod).
     |  
     |  __rsub__(self, value, /)
     |      Return value-self.
     |  
     |  __rtruediv__(self, value, /)
     |      Return value/self.
     |  
     |  __str__(self, /)
     |      Return str(self).
     |  
     |  __sub__(self, value, /)
     |      Return self-value.
     |  
     |  __truediv__(self, value, /)
     |      Return self/value.
     |  
     |  __trunc__(self, /)
     |      Return the Integral closest to x between 0 and x.
     |  
     |  as_integer_ratio(self, /)
     |      Return integer ratio.
     |      
     |      Return a pair of integers, whose ratio is exactly equal to the original float
     |      and with a positive denominator.
     |      
     |      Raise OverflowError on infinities and a ValueError on NaNs.
     |      
     |      >>> (10.0).as_integer_ratio()
     |      (10, 1)
     |      >>> (0.0).as_integer_ratio()
     |      (0, 1)
     |      >>> (-.25).as_integer_ratio()
     |      (-1, 4)
     |  
     |  conjugate(self, /)
     |      Return self, the complex conjugate of any float.
     |  
     |  hex(self, /)
     |      Return a hexadecimal representation of a floating-point number.
     |      
     |      >>> (-0.1).hex()
     |      '-0x1.999999999999ap-4'
     |      >>> 3.14159.hex()
     |      '0x1.921f9f01b866ep+1'
     |  
     |  is_integer(self, /)
     |      Return True if the float is an integer.
     |  
     |  ----------------------------------------------------------------------
     |  Class methods defined here:
     |  
     |  __getformat__(typestr, /) from builtins.type
     |      You probably don't want to use this function.
     |      
     |        typestr
     |          Must be 'double' or 'float'.
     |      
     |      It exists mainly to be used in Python's test suite.
     |      
     |      This function returns whichever of 'unknown', 'IEEE, big-endian' or 'IEEE,
     |      little-endian' best describes the format of floating point numbers used by the
     |      C type named by typestr.
     |  
     |  __set_format__(typestr, fmt, /) from builtins.type
     |      You probably don't want to use this function.
     |      
     |        typestr
     |          Must be 'double' or 'float'.
     |        fmt
     |          Must be one of 'unknown', 'IEEE, big-endian' or 'IEEE, little-endian',
     |          and in addition can only be one of the latter two if it appears to
     |          match the underlying C reality.
     |      
     |      It exists mainly to be used in Python's test suite.
     |      
     |      Override the automatic determination of C-level floating point type.
     |      This affects how floats are converted to and from binary strings.
     |  
     |  fromhex(string, /) from builtins.type
     |      Create a floating-point number from a hexadecimal string.
     |      
     |      >>> float.fromhex('0x1.ffffp10')
     |      2047.984375
     |      >>> float.fromhex('-0x1p-1074')
     |      -5e-324
     |  
     |  ----------------------------------------------------------------------
     |  Static methods defined here:
     |  
     |  __new__(*args, **kwargs) from builtins.type
     |      Create and return a new object.  See help(type) for accurate signature.
     |  
     |  ----------------------------------------------------------------------
     |  Data descriptors defined here:
     |  
     |  imag
     |      the imaginary part of a complex number
     |  
     |  real
     |      the real part of a complex number
    View Code
    Help on class complex in module builtins:
    
    class complex(object)
     |  complex(real=0, imag=0)
     |  
     |  Create a complex number from a real part and an optional imaginary part.
     |  
     |  This is equivalent to (real + imag*1j) where imag defaults to 0.
     |  
     |  Methods defined here:
     |  
     |  __abs__(self, /)
     |      abs(self)
     |  
     |  __add__(self, value, /)
     |      Return self+value.
     |  
     |  __bool__(self, /)
     |      self != 0
     |  
     |  __divmod__(self, value, /)
     |      Return divmod(self, value).
     |  
     |  __eq__(self, value, /)
     |      Return self==value.
     |  
     |  __float__(self, /)
     |      float(self)
     |  
     |  __floordiv__(self, value, /)
     |      Return self//value.
     |  
     |  __format__(...)
     |      complex.__format__() -> str
     |      
     |      Convert to a string according to format_spec.
     |  
     |  __ge__(self, value, /)
     |      Return self>=value.
     |  
     |  __getattribute__(self, name, /)
     |      Return getattr(self, name).
     |  
     |  __getnewargs__(...)
     |  
     |  __gt__(self, value, /)
     |      Return self>value.
     |  
     |  __hash__(self, /)
     |      Return hash(self).
     |  
     |  __int__(self, /)
     |      int(self)
     |  
     |  __le__(self, value, /)
     |      Return self<=value.
     |  
     |  __lt__(self, value, /)
     |      Return self<value.
     |  
     |  __mod__(self, value, /)
     |      Return self%value.
     |  
     |  __mul__(self, value, /)
     |      Return self*value.
     |  
     |  __ne__(self, value, /)
     |      Return self!=value.
     |  
     |  __neg__(self, /)
     |      -self
     |  
     |  __pos__(self, /)
     |      +self
     |  
     |  __pow__(self, value, mod=None, /)
     |      Return pow(self, value, mod).
     |  
     |  __radd__(self, value, /)
     |      Return value+self.
     |  
     |  __rdivmod__(self, value, /)
     |      Return divmod(value, self).
     |  
     |  __repr__(self, /)
     |      Return repr(self).
     |  
     |  __rfloordiv__(self, value, /)
     |      Return value//self.
     |  
     |  __rmod__(self, value, /)
     |      Return value%self.
     |  
     |  __rmul__(self, value, /)
     |      Return value*self.
     |  
     |  __rpow__(self, value, mod=None, /)
     |      Return pow(value, self, mod).
     |  
     |  __rsub__(self, value, /)
     |      Return value-self.
     |  
     |  __rtruediv__(self, value, /)
     |      Return value/self.
     |  
     |  __str__(self, /)
     |      Return str(self).
     |  
     |  __sub__(self, value, /)
     |      Return self-value.
     |  
     |  __truediv__(self, value, /)
     |      Return self/value.
     |  
     |  conjugate(...)
     |      complex.conjugate() -> complex
     |      
     |      Return the complex conjugate of its argument. (3-4j).conjugate() == 3+4j.
     |  
     |  ----------------------------------------------------------------------
     |  Static methods defined here:
     |  
     |  __new__(*args, **kwargs) from builtins.type
     |      Create and return a new object.  See help(type) for accurate signature.
     |  
     |  ----------------------------------------------------------------------
     |  Data descriptors defined here:
     |  
     |  imag
     |      the imaginary part of a complex number
     |  
     |  real
     |      the real part of a complex number
    View Code

    2、布尔值
      真或假
      1 或 0

    3、字符串
    var1 = 'Hello World!'
    var2 = "Hello World!"
    字符串常用功能:
    • 移除空白
    • 分割
    • 长度
    • 索引
    • 切片
    Help on class str in module builtins:
    
    class str(object)
     |  str(object='') -> str
     |  str(bytes_or_buffer[, encoding[, errors]]) -> str
     |  
     |  Create a new string object from the given object. If encoding or
     |  errors is specified, then the object must expose a data buffer
     |  that will be decoded using the given encoding and error handler.
     |  Otherwise, returns the result of object.__str__() (if defined)
     |  or repr(object).
     |  encoding defaults to sys.getdefaultencoding().
     |  errors defaults to 'strict'.
     |  
     |  Methods defined here:
     |  
     |  __add__(self, value, /)
     |      Return self+value.
     |  
     |  __contains__(self, key, /)
     |      Return key in self.
     |  
     |  __eq__(self, value, /)
     |      Return self==value.
     |  
     |  __format__(self, format_spec, /)
     |      Return a formatted version of the string as described by format_spec.
     |  
     |  __ge__(self, value, /)
     |      Return self>=value.
     |  
     |  __getattribute__(self, name, /)
     |      Return getattr(self, name).
     |  
     |  __getitem__(self, key, /)
     |      Return self[key].
     |  
     |  __getnewargs__(...)
     |  
     |  __gt__(self, value, /)
     |      Return self>value.
     |  
     |  __hash__(self, /)
     |      Return hash(self).
     |  
     |  __iter__(self, /)
     |      Implement iter(self).
     |  
     |  __le__(self, value, /)
     |      Return self<=value.
     |  
     |  __len__(self, /)
     |      Return len(self).
     |  
     |  __lt__(self, value, /)
     |      Return self<value.
     |  
     |  __mod__(self, value, /)
     |      Return self%value.
     |  
     |  __mul__(self, value, /)
     |      Return self*value.
     |  
     |  __ne__(self, value, /)
     |      Return self!=value.
     |  
     |  __repr__(self, /)
     |      Return repr(self).
     |  
     |  __rmod__(self, value, /)
     |      Return value%self.
     |  
     |  __rmul__(self, value, /)
     |      Return value*self.
     |  
     |  __sizeof__(self, /)
     |      Return the size of the string in memory, in bytes.
     |  
     |  __str__(self, /)
     |      Return str(self).
     |  
     |  capitalize(self, /)
     |      Return a capitalized version of the string.
     |      
     |      More specifically, make the first character have upper case and the rest lower
     |      case.
     |  
     |  casefold(self, /)
     |      Return a version of the string suitable for caseless comparisons.
     |  
     |  center(self, width, fillchar=' ', /)
     |      Return a centered string of length width.
     |      
     |      Padding is done using the specified fill character (default is a space).
     |  
     |  count(...)
     |      S.count(sub[, start[, end]]) -> int
     |      
     |      Return the number of non-overlapping occurrences of substring sub in
     |      string S[start:end].  Optional arguments start and end are
     |      interpreted as in slice notation.
     |  
     |  encode(self, /, encoding='utf-8', errors='strict')
     |      Encode the string using the codec registered for encoding.
     |      
     |      encoding
     |        The encoding in which to encode the string.
     |      errors
     |        The error handling scheme to use for encoding errors.
     |        The default is 'strict' meaning that encoding errors raise a
     |        UnicodeEncodeError.  Other possible values are 'ignore', 'replace' and
     |        'xmlcharrefreplace' as well as any other name registered with
     |        codecs.register_error that can handle UnicodeEncodeErrors.
     |  
     |  endswith(...)
     |      S.endswith(suffix[, start[, end]]) -> bool
     |      
     |      Return True if S ends with the specified suffix, False otherwise.
     |      With optional start, test S beginning at that position.
     |      With optional end, stop comparing S at that position.
     |      suffix can also be a tuple of strings to try.
     |  
     |  expandtabs(self, /, tabsize=8)
     |      Return a copy where all tab characters are expanded using spaces.
     |      
     |      If tabsize is not given, a tab size of 8 characters is assumed.
     |  
     |  find(...)
     |      S.find(sub[, start[, end]]) -> int
     |      
     |      Return the lowest index in S where substring sub is found,
     |      such that sub is contained within S[start:end].  Optional
     |      arguments start and end are interpreted as in slice notation.
     |      
     |      Return -1 on failure.
     |  
     |  format(...)
     |      S.format(*args, **kwargs) -> str
     |      
     |      Return a formatted version of S, using substitutions from args and kwargs.
     |      The substitutions are identified by braces ('{' and '}').
     |  
     |  format_map(...)
     |      S.format_map(mapping) -> str
     |      
     |      Return a formatted version of S, using substitutions from mapping.
     |      The substitutions are identified by braces ('{' and '}').
     |  
     |  index(...)
     |      S.index(sub[, start[, end]]) -> int
     |      
     |      Return the lowest index in S where substring sub is found, 
     |      such that sub is contained within S[start:end].  Optional
     |      arguments start and end are interpreted as in slice notation.
     |      
     |      Raises ValueError when the substring is not found.
     |  
     |  isalnum(self, /)
     |      Return True if the string is an alpha-numeric string, False otherwise.
     |      
     |      A string is alpha-numeric if all characters in the string are alpha-numeric and
     |      there is at least one character in the string.
     |  
     |  isalpha(self, /)
     |      Return True if the string is an alphabetic string, False otherwise.
     |      
     |      A string is alphabetic if all characters in the string are alphabetic and there
     |      is at least one character in the string.
     |  
     |  isascii(self, /)
     |      Return True if all characters in the string are ASCII, False otherwise.
     |      
     |      ASCII characters have code points in the range U+0000-U+007F.
     |      Empty string is ASCII too.
     |  
     |  isdecimal(self, /)
     |      Return True if the string is a decimal string, False otherwise.
     |      
     |      A string is a decimal string if all characters in the string are decimal and
     |      there is at least one character in the string.
     |  
     |  isdigit(self, /)
     |      Return True if the string is a digit string, False otherwise.
     |      
     |      A string is a digit string if all characters in the string are digits and there
     |      is at least one character in the string.
     |  
     |  isidentifier(self, /)
     |      Return True if the string is a valid Python identifier, False otherwise.
     |      
     |      Use keyword.iskeyword() to test for reserved identifiers such as "def" and
     |      "class".
     |  
     |  islower(self, /)
     |      Return True if the string is a lowercase string, False otherwise.
     |      
     |      A string is lowercase if all cased characters in the string are lowercase and
     |      there is at least one cased character in the string.
     |  
     |  isnumeric(self, /)
     |      Return True if the string is a numeric string, False otherwise.
     |      
     |      A string is numeric if all characters in the string are numeric and there is at
     |      least one character in the string.
     |  
     |  isprintable(self, /)
     |      Return True if the string is printable, False otherwise.
     |      
     |      A string is printable if all of its characters are considered printable in
     |      repr() or if it is empty.
     |  
     |  isspace(self, /)
     |      Return True if the string is a whitespace string, False otherwise.
     |      
     |      A string is whitespace if all characters in the string are whitespace and there
     |      is at least one character in the string.
     |  
     |  istitle(self, /)
     |      Return True if the string is a title-cased string, False otherwise.
     |      
     |      In a title-cased string, upper- and title-case characters may only
     |      follow uncased characters and lowercase characters only cased ones.
     |  
     |  isupper(self, /)
     |      Return True if the string is an uppercase string, False otherwise.
     |      
     |      A string is uppercase if all cased characters in the string are uppercase and
     |      there is at least one cased character in the string.
     |  
     |  join(self, iterable, /)
     |      Concatenate any number of strings.
     |      
     |      The string whose method is called is inserted in between each given string.
     |      The result is returned as a new string.
     |      
     |      Example: '.'.join(['ab', 'pq', 'rs']) -> 'ab.pq.rs'
     |  
     |  ljust(self, width, fillchar=' ', /)
     |      Return a left-justified string of length width.
     |      
     |      Padding is done using the specified fill character (default is a space).
     |  
     |  lower(self, /)
     |      Return a copy of the string converted to lowercase.
     |  
     |  lstrip(self, chars=None, /)
     |      Return a copy of the string with leading whitespace removed.
     |      
     |      If chars is given and not None, remove characters in chars instead.
     |  
     |  partition(self, sep, /)
     |      Partition the string into three parts using the given separator.
     |      
     |      This will search for the separator in the string.  If the separator is found,
     |      returns a 3-tuple containing the part before the separator, the separator
     |      itself, and the part after it.
     |      
     |      If the separator is not found, returns a 3-tuple containing the original string
     |      and two empty strings.
     |  
     |  replace(self, old, new, count=-1, /)
     |      Return a copy with all occurrences of substring old replaced by new.
     |      
     |        count
     |          Maximum number of occurrences to replace.
     |          -1 (the default value) means replace all occurrences.
     |      
     |      If the optional argument count is given, only the first count occurrences are
     |      replaced.
     |  
     |  rfind(...)
     |      S.rfind(sub[, start[, end]]) -> int
     |      
     |      Return the highest index in S where substring sub is found,
     |      such that sub is contained within S[start:end].  Optional
     |      arguments start and end are interpreted as in slice notation.
     |      
     |      Return -1 on failure.
     |  
     |  rindex(...)
     |      S.rindex(sub[, start[, end]]) -> int
     |      
     |      Return the highest index in S where substring sub is found,
     |      such that sub is contained within S[start:end].  Optional
     |      arguments start and end are interpreted as in slice notation.
     |      
     |      Raises ValueError when the substring is not found.
     |  
     |  rjust(self, width, fillchar=' ', /)
     |      Return a right-justified string of length width.
     |      
     |      Padding is done using the specified fill character (default is a space).
     |  
     |  rpartition(self, sep, /)
     |      Partition the string into three parts using the given separator.
     |      
     |      This will search for the separator in the string, starting at the end. If
     |      the separator is found, returns a 3-tuple containing the part before the
     |      separator, the separator itself, and the part after it.
     |      
     |      If the separator is not found, returns a 3-tuple containing two empty strings
     |      and the original string.
     |  
     |  rsplit(self, /, sep=None, maxsplit=-1)
     |      Return a list of the words in the string, using sep as the delimiter string.
     |      
     |        sep
     |          The delimiter according which to split the string.
     |          None (the default value) means split according to any whitespace,
     |          and discard empty strings from the result.
     |        maxsplit
     |          Maximum number of splits to do.
     |          -1 (the default value) means no limit.
     |      
     |      Splits are done starting at the end of the string and working to the front.
     |  
     |  rstrip(self, chars=None, /)
     |      Return a copy of the string with trailing whitespace removed.
     |      
     |      If chars is given and not None, remove characters in chars instead.
     |  
     |  split(self, /, sep=None, maxsplit=-1)
     |      Return a list of the words in the string, using sep as the delimiter string.
     |      
     |      sep
     |        The delimiter according which to split the string.
     |        None (the default value) means split according to any whitespace,
     |        and discard empty strings from the result.
     |      maxsplit
     |        Maximum number of splits to do.
     |        -1 (the default value) means no limit.
     |  
     |  splitlines(self, /, keepends=False)
     |      Return a list of the lines in the string, breaking at line boundaries.
     |      
     |      Line breaks are not included in the resulting list unless keepends is given and
     |      true.
     |  
     |  startswith(...)
     |      S.startswith(prefix[, start[, end]]) -> bool
     |      
     |      Return True if S starts with the specified prefix, False otherwise.
     |      With optional start, test S beginning at that position.
     |      With optional end, stop comparing S at that position.
     |      prefix can also be a tuple of strings to try.
     |  
     |  strip(self, chars=None, /)
     |      Return a copy of the string with leading and trailing whitespace remove.
     |      
     |      If chars is given and not None, remove characters in chars instead.
     |  
     |  swapcase(self, /)
     |      Convert uppercase characters to lowercase and lowercase characters to uppercase.
     |  
     |  title(self, /)
     |      Return a version of the string where each word is titlecased.
     |      
     |      More specifically, words start with uppercased characters and all remaining
     |      cased characters have lower case.
     |  
     |  translate(self, table, /)
     |      Replace each character in the string using the given translation table.
     |      
     |        table
     |          Translation table, which must be a mapping of Unicode ordinals to
     |          Unicode ordinals, strings, or None.
     |      
     |      The table must implement lookup/indexing via __getitem__, for instance a
     |      dictionary or list.  If this operation raises LookupError, the character is
     |      left untouched.  Characters mapped to None are deleted.
     |  
     |  upper(self, /)
     |      Return a copy of the string converted to uppercase.
     |  
     |  zfill(self, width, /)
     |      Pad a numeric string with zeros on the left, to fill a field of the given width.
     |      
     |      The string is never truncated.
     |  
     |  ----------------------------------------------------------------------
     |  Static methods defined here:
     |  
     |  __new__(*args, **kwargs) from builtins.type
     |      Create and return a new object.  See help(type) for accurate signature.
     |  
     |  maketrans(x, y=None, z=None, /)
     |      Return a translation table usable for str.translate().
     |      
     |      If there is only one argument, it must be a dictionary mapping Unicode
     |      ordinals (integers) or characters to Unicode ordinals, strings or None.
     |      Character keys will be then converted to ordinals.
     |      If there are two arguments, they must be strings of equal length, and
     |      in the resulting dictionary, each character in x will be mapped to the
     |      character at the same position in y. If there is a third argument, it
     |      must be a string, whose characters will be mapped to None in the result.
    View Code

    4、列表
    创建列表:
    name_list = ['alex', 'seven', 'eric']
    或
    name_list = list(['alex', 'seven', 'eric'])
    Help on class list in module builtins:
    
    class list(object)
     |  list(iterable=(), /)
     |  
     |  Built-in mutable sequence.
     |  
     |  If no argument is given, the constructor creates a new empty list.
     |  The argument must be an iterable if specified.
     |  
     |  Methods defined here:
     |  
     |  __add__(self, value, /)
     |      Return self+value.
     |  
     |  __contains__(self, key, /)
     |      Return key in self.
     |  
     |  __delitem__(self, key, /)
     |      Delete self[key].
     |  
     |  __eq__(self, value, /)
     |      Return self==value.
     |  
     |  __ge__(self, value, /)
     |      Return self>=value.
     |  
     |  __getattribute__(self, name, /)
     |      Return getattr(self, name).
     |  
     |  __getitem__(...)
     |      x.__getitem__(y) <==> x[y]
     |  
     |  __gt__(self, value, /)
     |      Return self>value.
     |  
     |  __iadd__(self, value, /)
     |      Implement self+=value.
     |  
     |  __imul__(self, value, /)
     |      Implement self*=value.
     |  
     |  __init__(self, /, *args, **kwargs)
     |      Initialize self.  See help(type(self)) for accurate signature.
     |  
     |  __iter__(self, /)
     |      Implement iter(self).
     |  
     |  __le__(self, value, /)
     |      Return self<=value.
     |  
     |  __len__(self, /)
     |      Return len(self).
     |  
     |  __lt__(self, value, /)
     |      Return self<value.
     |  
     |  __mul__(self, value, /)
     |      Return self*value.
     |  
     |  __ne__(self, value, /)
     |      Return self!=value.
     |  
     |  __repr__(self, /)
     |      Return repr(self).
     |  
     |  __reversed__(self, /)
     |      Return a reverse iterator over the list.
     |  
     |  __rmul__(self, value, /)
     |      Return value*self.
     |  
     |  __setitem__(self, key, value, /)
     |      Set self[key] to value.
     |  
     |  __sizeof__(self, /)
     |      Return the size of the list in memory, in bytes.
     |  
     |  append(self, object, /)
     |      Append object to the end of the list.
     |  
     |  clear(self, /)
     |      Remove all items from list.
     |  
     |  copy(self, /)
     |      Return a shallow copy of the list.
     |  
     |  count(self, value, /)
     |      Return number of occurrences of value.
     |  
     |  extend(self, iterable, /)
     |      Extend list by appending elements from the iterable.
     |  
     |  index(self, value, start=0, stop=9223372036854775807, /)
     |      Return first index of value.
     |      
     |      Raises ValueError if the value is not present.
     |  
     |  insert(self, index, object, /)
     |      Insert object before index.
     |  
     |  pop(self, index=-1, /)
     |      Remove and return item at index (default last).
     |      
     |      Raises IndexError if list is empty or index is out of range.
     |  
     |  remove(self, value, /)
     |      Remove first occurrence of value.
     |      
     |      Raises ValueError if the value is not present.
     |  
     |  reverse(self, /)
     |      Reverse *IN PLACE*.
     |  
     |  sort(self, /, *, key=None, reverse=False)
     |      Stable sort *IN PLACE*.
     |  
     |  ----------------------------------------------------------------------
     |  Static methods defined here:
     |  
     |  __new__(*args, **kwargs) from builtins.type
     |      Create and return a new object.  See help(type) for accurate signature.
     |  
     |  ----------------------------------------------------------------------
     |  Data and other attributes defined here:
     |  
     |  __hash__ = None
    View Code

    5、元祖
    创建元祖:
    ages = (11, 22, 33, 44, 55)
    或
    ages = tuple((11, 22, 33, 44, 55))
    基本操作:
    • 索引
    • 切片
    • 循环
    • 长度
    • 包含
    Help on class tuple in module builtins:
    
    class tuple(object)
     |  tuple(iterable=(), /)
     |  
     |  Built-in immutable sequence.
     |  
     |  If no argument is given, the constructor returns an empty tuple.
     |  If iterable is specified the tuple is initialized from iterable's items.
     |  
     |  If the argument is a tuple, the return value is the same object.
     |  
     |  Methods defined here:
     |  
     |  __add__(self, value, /)
     |      Return self+value.
     |  
     |  __contains__(self, key, /)
     |      Return key in self.
     |  
     |  __eq__(self, value, /)
     |      Return self==value.
     |  
     |  __ge__(self, value, /)
     |      Return self>=value.
     |  
     |  __getattribute__(self, name, /)
     |      Return getattr(self, name).
     |  
     |  __getitem__(self, key, /)
     |      Return self[key].
     |  
     |  __getnewargs__(self, /)
     |  
     |  __gt__(self, value, /)
     |      Return self>value.
     |  
     |  __hash__(self, /)
     |      Return hash(self).
     |  
     |  __iter__(self, /)
     |      Implement iter(self).
     |  
     |  __le__(self, value, /)
     |      Return self<=value.
     |  
     |  __len__(self, /)
     |      Return len(self).
     |  
     |  __lt__(self, value, /)
     |      Return self<value.
     |  
     |  __mul__(self, value, /)
     |      Return self*value.
     |  
     |  __ne__(self, value, /)
     |      Return self!=value.
     |  
     |  __repr__(self, /)
     |      Return repr(self).
     |  
     |  __rmul__(self, value, /)
     |      Return value*self.
     |  
     |  count(self, value, /)
     |      Return number of occurrences of value.
     |  
     |  index(self, value, start=0, stop=9223372036854775807, /)
     |      Return first index of value.
     |      
     |      Raises ValueError if the value is not present.
     |  
     |  ----------------------------------------------------------------------
     |  Static methods defined here:
     |  
     |  __new__(*args, **kwargs) from builtins.type
     |      Create and return a new object.  See help(type) for accurate signature.
    View Code

    6、字典(无序)
    创建字典:
    person = {"name": "mr.wu", 'age': 18}
    或
    person = dict({"name": "mr.wu", 'age': 18})
    Help on class dict in module builtins:
    
    class dict(object)
     |  dict() -> new empty dictionary
     |  dict(mapping) -> new dictionary initialized from a mapping object's
     |      (key, value) pairs
     |  dict(iterable) -> new dictionary initialized as if via:
     |      d = {}
     |      for k, v in iterable:
     |          d[k] = v
     |  dict(**kwargs) -> new dictionary initialized with the name=value pairs
     |      in the keyword argument list.  For example:  dict(one=1, two=2)
     |  
     |  Methods defined here:
     |  
     |  __contains__(self, key, /)
     |      True if the dictionary has the specified key, else False.
     |  
     |  __delitem__(self, key, /)
     |      Delete self[key].
     |  
     |  __eq__(self, value, /)
     |      Return self==value.
     |  
     |  __ge__(self, value, /)
     |      Return self>=value.
     |  
     |  __getattribute__(self, name, /)
     |      Return getattr(self, name).
     |  
     |  __getitem__(...)
     |      x.__getitem__(y) <==> x[y]
     |  
     |  __gt__(self, value, /)
     |      Return self>value.
     |  
     |  __init__(self, /, *args, **kwargs)
     |      Initialize self.  See help(type(self)) for accurate signature.
     |  
     |  __iter__(self, /)
     |      Implement iter(self).
     |  
     |  __le__(self, value, /)
     |      Return self<=value.
     |  
     |  __len__(self, /)
     |      Return len(self).
     |  
     |  __lt__(self, value, /)
     |      Return self<value.
     |  
     |  __ne__(self, value, /)
     |      Return self!=value.
     |  
     |  __repr__(self, /)
     |      Return repr(self).
     |  
     |  __setitem__(self, key, value, /)
     |      Set self[key] to value.
     |  
     |  __sizeof__(...)
     |      D.__sizeof__() -> size of D in memory, in bytes
     |  
     |  clear(...)
     |      D.clear() -> None.  Remove all items from D.
     |  
     |  copy(...)
     |      D.copy() -> a shallow copy of D
     |  
     |  get(self, key, default=None, /)
     |      Return the value for key if key is in the dictionary, else default.
     |  
     |  items(...)
     |      D.items() -> a set-like object providing a view on D's items
     |  
     |  keys(...)
     |      D.keys() -> a set-like object providing a view on D's keys
     |  
     |  pop(...)
     |      D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
     |      If key is not found, d is returned if given, otherwise KeyError is raised
     |  
     |  popitem(...)
     |      D.popitem() -> (k, v), remove and return some (key, value) pair as a
     |      2-tuple; but raise KeyError if D is empty.
     |  
     |  setdefault(self, key, default=None, /)
     |      Insert key with a value of default if key is not in the dictionary.
     |      
     |      Return the value for key if key is in the dictionary, else default.
     |  
     |  update(...)
     |      D.update([E, ]**F) -> None.  Update D from dict/iterable E and F.
     |      If E is present and has a .keys() method, then does:  for k in E: D[k] = E[k]
     |      If E is present and lacks a .keys() method, then does:  for k, v in E: D[k] = v
     |      In either case, this is followed by: for k in F:  D[k] = F[k]
     |  
     |  values(...)
     |      D.values() -> an object providing a view on D's values
     |  
     |  ----------------------------------------------------------------------
     |  Class methods defined here:
     |  
     |  fromkeys(iterable, value=None, /) from builtins.type
     |      Create a new dictionary with keys from iterable and values set to value.
     |  
     |  ----------------------------------------------------------------------
     |  Static methods defined here:
     |  
     |  __new__(*args, **kwargs) from builtins.type
     |      Create and return a new object.  See help(type) for accurate signature.
     |  
     |  ----------------------------------------------------------------------
     |  Data and other attributes defined here:
     |  
     |  __hash__ = None
    View Code

    7、set

    set集合,是一个无序且不重复的元素集合

    Help on class set in module builtins:
    
    class set(object)
     |  set() -> new empty set object
     |  set(iterable) -> new set object
     |  
     |  Build an unordered collection of unique elements.
     |  
     |  Methods defined here:
     |  
     |  __and__(self, value, /)
     |      Return self&value.
     |  
     |  __contains__(...)
     |      x.__contains__(y) <==> y in x.
     |  
     |  __eq__(self, value, /)
     |      Return self==value.
     |  
     |  __ge__(self, value, /)
     |      Return self>=value.
     |  
     |  __getattribute__(self, name, /)
     |      Return getattr(self, name).
     |  
     |  __gt__(self, value, /)
     |      Return self>value.
     |  
     |  __iand__(self, value, /)
     |      Return self&=value.
     |  
     |  __init__(self, /, *args, **kwargs)
     |      Initialize self.  See help(type(self)) for accurate signature.
     |  
     |  __ior__(self, value, /)
     |      Return self|=value.
     |  
     |  __isub__(self, value, /)
     |      Return self-=value.
     |  
     |  __iter__(self, /)
     |      Implement iter(self).
     |  
     |  __ixor__(self, value, /)
     |      Return self^=value.
     |  
     |  __le__(self, value, /)
     |      Return self<=value.
     |  
     |  __len__(self, /)
     |      Return len(self).
     |  
     |  __lt__(self, value, /)
     |      Return self<value.
     |  
     |  __ne__(self, value, /)
     |      Return self!=value.
     |  
     |  __or__(self, value, /)
     |      Return self|value.
     |  
     |  __rand__(self, value, /)
     |      Return value&self.
     |  
     |  __reduce__(...)
     |      Return state information for pickling.
     |  
     |  __repr__(self, /)
     |      Return repr(self).
     |  
     |  __ror__(self, value, /)
     |      Return value|self.
     |  
     |  __rsub__(self, value, /)
     |      Return value-self.
     |  
     |  __rxor__(self, value, /)
     |      Return value^self.
     |  
     |  __sizeof__(...)
     |      S.__sizeof__() -> size of S in memory, in bytes
     |  
     |  __sub__(self, value, /)
     |      Return self-value.
     |  
     |  __xor__(self, value, /)
     |      Return self^value.
     |  
     |  add(...)
     |      Add an element to a set.
     |      
     |      This has no effect if the element is already present.
     |  
     |  clear(...)
     |      Remove all elements from this set.
     |  
     |  copy(...)
     |      Return a shallow copy of a set.
     |  
     |  difference(...)
     |      Return the difference of two or more sets as a new set.
     |      
     |      (i.e. all elements that are in this set but not the others.)
     |  
     |  difference_update(...)
     |      Remove all elements of another set from this set.
     |  
     |  discard(...)
     |      Remove an element from a set if it is a member.
     |      
     |      If the element is not a member, do nothing.
     |  
     |  intersection(...)
     |      Return the intersection of two sets as a new set.
     |      
     |      (i.e. all elements that are in both sets.)
     |  
     |  intersection_update(...)
     |      Update a set with the intersection of itself and another.
     |  
     |  isdisjoint(...)
     |      Return True if two sets have a null intersection.
     |  
     |  issubset(...)
     |      Report whether another set contains this set.
     |  
     |  issuperset(...)
     |      Report whether this set contains another set.
     |  
     |  pop(...)
     |      Remove and return an arbitrary set element.
     |      Raises KeyError if the set is empty.
     |  
     |  remove(...)
     |      Remove an element from a set; it must be a member.
     |      
     |      If the element is not a member, raise a KeyError.
     |  
     |  symmetric_difference(...)
     |      Return the symmetric difference of two sets as a new set.
     |      
     |      (i.e. all elements that are in exactly one of the sets.)
     |  
     |  symmetric_difference_update(...)
     |      Update a set with the symmetric difference of itself and another.
     |  
     |  union(...)
     |      Return the union of sets as a new set.
     |      
     |      (i.e. all elements that are in either set.)
     |  
     |  update(...)
     |      Update a set with the union of itself and others.
     |  
     |  ----------------------------------------------------------------------
     |  Static methods defined here:
     |  
     |  __new__(*args, **kwargs) from builtins.type
     |      Create and return a new object.  See help(type) for accurate signature.
     |  
     |  ----------------------------------------------------------------------
     |  Data and other attributes defined here:
     |  
     |  __hash__ = None
    View Code
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  • 原文地址:https://www.cnblogs.com/whxutao/p/10151901.html
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