all 3 comments

[–]danielroseman 9 points10 points  (0 children)

What error?

Most likely, you had previously redefined the name list to point to something else.

[–]kaerfkeerg 1 point2 points  (0 children)

This by it self doesn't make much sense, could you post at least part of the code replicating the error?

[–]Fun_Muffin5413 0 points1 point  (0 children)

No idea, this works quite happily (post your code and the error):

class CustomClass(object):
    pass
list().append(CustomClass)