python_Exception之：TypeError: 'int' object is not iterable

>>> for D in range(10):
...     for i in D:        #for i in 0:（0不可被迭代）   
...        values=[]
...        values.append((i,'str'+str(i)))
...        print values
...
Traceback (most recent call last):
  File "<stdin>", line 2, in <module>
TypeError: 'int' object is not iterable

>>> D=[0,1,2,3,4,5,6,7,8,9]  #可迭代对象
>>> for i in D:        
...     values=[]
...     values.append((i,'str'+str(i)))    #values.append((i,'str'+i))  -->TypeError: cannot concatenate 'str' and 'int' objects
...     print values
...
[(0, 'str0')]
[(1, 'str1')]
[(2, 'str2')]
[(3, 'str3')]
[(4, 'str4')]
[(5, 'str5')]
[(6, 'str6')]
[(7, 'str7')]
[(8, 'str8')]
[(9, 'str9')]

>>>