def f1():
pass
f1()
f2 = 123
f2()
1、callable()
print(callable(f1)) 可执行为True
print(callable(f2)) 否则为False
2、
chr() 数字转换为字符
ord() 字符转换为数字
r = chr(65)
print(r) 结果为 A
n = ord("a")
print(n) 结果为97
获取随机字母验证码
# 1=<i<5
# i = random.randrange(65, 91)
# c = chr(i)
# print(c) 一位随机字母
li=[]
for i in range(6):
i = random.randrange(65, 91)
c = chr(i)
li.append(c)
print("".join(li)) 6位随机字母验证码
# import random
# li = []
# for i in range(6): 字母数字混合验证码
# if i ==2 or i == 4:
# num = random.randrange(0, 10)
# li.append(str(num))
# else:
# temp = random.randrange(65, 91)
# c = chr(temp)
# li.append(c)
#
# result = "".join(li)
# print(result)
3、
compile() 将source编译为代码或者AST对象。代码对象能够通过exec语句来执行或者eval()进行求值。
eval() 执行动作并返回结果
exec() 一个动作
s = "print(123)"
# 编译，single，eval，exec
# 将字符串编译成python代码
# r = compile(s, "<string>", "exec")
# 执行python代码
# exec(r)
# s = "8*8"
# ret = eval(s)
# print(ret)
# 将字符串，编译成python代码
# compile()
#执行python代码，接收：代码或者字符串
# exec("7+9+8")
#执行表达式，并且获取结果
# ret = eval("7+9+8")
# print(ret)
4、dir() 快速查看，对象提供了那些功能
# print(dir(list))
# help(list)
5、divmod() 计算除法的整数位 余数
# 共：97， 每页显示10条，需要多少页
# r = divmod(100, 10)
# print(r[0])
# print(r[1]) r0是整数位 r1是余数
# n1, n2 = divmod(100, 10)
6、isinstance() 对象是否是某个类的实例
# s = "alex" # 对象，"alex" => str
# s = [11,11,11]
# # 用于判断，对象是否是某个类的实例
# r = isinstance(s, list)
# print(r)
7、 filter ，循环循环第二个参数，让每个循环元素执行一个参数，如果返回值True，表示元素合法
print(filter(lambda a: a>22,[11,22,33,44,55]))
print(list( filter(lambda a: a>22,[11,22,33,44,55])))
# def f1(args):
# result = []
# for item in args:
# if item > 22:
# result.append(item)
# return result
#
# li = [11, 22, 33, 44, 55]
# ret = f1(li)
# print(ret)
# filter(函数，可迭代的对象)
# def f2(a):
# if a>22:
# return True
# li = [11, 22, 33, 44, 55]
# filter内部，循环第二个参数
# result = []
# for item in 第二个参数:
# r = 第一个参数(item)
# if r :
# result(item)
# return result
# filter ，循环循环第二个参数，让每个循环元素执行 函数，如果函数返回值True，表示元素合法
# ret = filter(f2, li)
# print(list(ret))
# filter,内部循环，参数比较
# 自动return
# f1 = lambda a: a > 30
#
# ret = f1(10)
# print(ret)
# li = [11, 22, 33, 44, 55]
# result = filter(lambda a: a > 33, li)
# print(list(result))
7、map()
print(map(lambda a: a+22,[11,22,33,44,55]))
print(list( map(lambda a: a+22,[11,22,33,44,55])))
# map
li = [11, 22, 33, 44, 55]
# map(函数，可迭代的对象(可以for循环的东西))
# def f2(a):
# return a + 100
# result = map(f2, li)
# result = map(lambda a: a + 200, li)
# print(list(result))
# filter # 函数返回True，将元素添加到结果中
# map # 将函数返回值添加到结果中
# def f1(args):
# result = []
# for i in args:
# result.append(100+i)
#
# return result
# r = f1(li)
# print(list(r))
8、locals() glocals()
# set
# NAME = "ALEX"
#
# def show():
# a = 123
# c = 123
# print(locals()) locals 是只读的，
# print(globals()) globals 不是
# show()
结果：{'a': 123, 'c': 123}
{'__cached__': None, '__doc__': None, '__name__': '__main__', 'NAME': '小三', '__spec__': None, '__builtins__': <module 'builtins' (built-in)>, '__package__': None, 'show': <function show at 0x021E1198>, '__loader__': <_fr ozen_importlib.SourceFileLoader object at 0x021A5730>, '__file__': 'C:/Users/
# s = "hhhasdfasdfasdfasdfasdfasdfasdfasdfasdfasdfasdfhhhasdfasdfasdfasdfasdfasdfasdfasdfasdfasdfasdf"
# dic = {
# 6366645726074670325:1
# }
# print(hash(s))
9、len() 长度
# s = "张三"
# print(len(s))
#
# s = "张三"
# b = bytes(s, encoding='utf-8')
# print(len(b))
# 2.7 for “张三” 长度4
# 3.5 for “张三” 长度6
10、sum() 求和
# r = sum([11,22,33,1])
# print(r)
# str,
11、 repr()
# r = repr("alex")
# print(r)
# li = [11,22,1,1]
#
# # li.reverse()
#
# reversed(li)
12、 round()
# r = round(1.4)
# print(r)
# s = "sssssssss"
# print(s[0:2:2])
13、sort() 排序
# li = [11,2,1,1]
# li.sort()
#
# sorted(li)
14、zip 每个列表同位置元素组合
# l1 = ["zhangsan", 11, 22, 33]
# l2 = ["is", 11, 22, 33]
# l3 = ["sb", 11, 22, 33]
#
# r = zip(l1, l2, l3)
# temp = list(r)[0]
# ret = ' '.join(temp)
# print(ret)