Karthikeyan Singaravelan <tir.kar...@gmail.com> added the comment:
You are appending to the class attribute where both shelf[0] and shelf[1] refers to the same list as seen by output of id. You might want to create an instance variable and use it for mutating across different instances. This could help : https://docs.python.org/3/tutorial/classes.html#class-and-instance-variables class Folder(): papers = [] def __init__(self): self.papers_self = [] shelf = [] shelf.append(Folder) shelf.append(Folder) print(f"{id(shelf[0]) = }") print(f"{id(shelf[1]) = }") shelf = [] shelf.append(Folder()) shelf.append(Folder()) print(f"{id(shelf[0].papers_self) = }") print(f"{id(shelf[1].papers_self) = }") shelf[0].papers_self.append("one") shelf[1].papers_self.append("two") print(f"{shelf[0].papers_self = }") print(f"{shelf[1].papers_self = }") id(shelf[0]) = 140411765635376 id(shelf[1]) = 140411765635376 id(shelf[0].papers_self) = 140411720636864 id(shelf[1].papers_self) = 140411720668608 shelf[0].papers_self = ['one'] shelf[1].papers_self = ['two'] ---------- nosy: +xtreak _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue39315> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
