确定python列表是相同的列表还是仅仅是等效的列表

Question

假设我有这样的代码：

a = [1,2]
b = [1,2]
def equivalentButDifferent(list1, list2):
# list1 and list2 are lists
return <is list1 and list2 the same or merely equivalent>

如何为equivalentButDifferent(a,b)返回True，为equivalentButDifferent(a,a)返回False？

Answer 1

正如@jonrsharpe在评论中所说，这将是函数：

a = [1,2]
b = [1,2]
def equivalentButDifferent(list1, list2):
return list1 == list2 and list1 is not list2

Answer 2

==或！=运营商比较股权价值。在这种情况下：

>>> a = [1,2]
>>> b = [1,2]
>>> a == b
True
>>> a != b
False

也就是说，a和b是相等的。

is和not is比较标识的值(如果它们相同(。

>>> a = [1,2]
>>> b = [1,2]
>>> c = a
>>> a is b
False
>>> a is c
True