python reverse 和reversed

没有完全明白,至少试出来了

>>> a=['I','like','python']
>>> help(reverse)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'reverse' is not defined
>>> a.reverse()
>>> a
['python', 'like', 'I']
>>> help(reversed)

>>> a=['I','like','python']
>>> id(a)
139942318019288
>>> a.reverse()
>>> id(a)
139942318019288
>>> a
['python', 'like', 'I']
>>> a.reversed()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'list' object has no attribute 'reversed'
>>> help(reversed)

>>> a.__getattribute_('b')_
  File "<stdin>", line 1
    a.__getattribute_('b')_
                          ^
SyntaxError: invalid syntax
>>> a.__getattribute__('b')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'list' object has no attribute 'b'
>>> a.__getattribute__('I')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'list' object has no attribute 'I'
>>> a
['python', 'like', 'I']
>>> a=I like python
  File "<stdin>", line 1
    a=I like python
           ^
SyntaxError: invalid syntax
>>> a
['python', 'like', 'I']
>>> reversed(a)
<listreverseiterator object at 0x7f46ddd20350>
>>> print list(reversed(a))
['I', 'like', 'python']
>>>

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转载自www.cnblogs.com/hsdchenliyang/p/9291621.html