def open(self, name, mode='rb', mixin=None):
        file = self._open(name, mode)
        if mixin:
            # Add the mixin as a parent class of the File returned from storage.
            file.__class__ = type(mixin.__name__, (mixin, file.__class__), {})
        return file
Retrieves the specified file from storage, using the optional mixin
dataset/ETHPy150Open dcramer/django-compositepks/django/core/files/storage.py/Storage.open