0.74.2

If a user created a custom Column subclass, then migrations would fail. For example:

class CustomColumn(Varchar):
    def __init__(self, custom_arg: str = '', *args, **kwargs):
        self.custom_arg = custom_arg
        super().__init__(*args, **kwargs)

    @property
    def column_type(self):
        return 'VARCHAR'

See PR 497. Thanks to @WintonLi for reporting this issue.