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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def setup(app):
 """Setup autodoc."""

    # Fix for documenting models.FileField
    from django.db.models.fields.files import FileDescriptor
    FileDescriptor.__get__ = lambda self, *args, **kwargs: self
    import django
    django.setup()
    app.connect('autodoc-skip-member', skip)
    app.add_stylesheet('_static/custom.css')