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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 remove(self,obj):
 """ Remove an object from the relation """

        relationship_table = self.params['relationship_table']
        with self.obj.backend.transaction(implicit = True):
            condition = and_(relationship_table.c[self.params['related_pk_field_name']] == obj.pk,
                             relationship_table.c[self.params['pk_field_name']] == self.obj.pk)
            self.obj.backend.connection.execute(delete(relationship_table).where(condition))
            self._queryset = None