str(list) calls __repr__ instead of __str__

gistfile1.txt

>>> class MyClass(object):
...     def __repr__(self):
...         return "repr"
...     def __str__(self):
...         return "str"
... 
>>> repr(MyClass())
'repr'
>>> str(MyClass())
'str'
>>> str([MyClass()])
'[repr]'
>>> repr([MyClass()])
'[repr]'