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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 delete_user_permissions(self, user, perm, obj, check_groups=False):
 """ Remove granular permission perm from user on an object instance """

        user_perms = self.user_permissions(user, perm, obj, check_groups=False)
        if not user_perms.filter(object_id=obj.id):
            return
        perms = self.user_permissions(user, perm, obj).filter(object_id=obj.id)
        perms.delete()