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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 collapse(self, id_user):
 """Collapse comment beloging to user."""

        c = CmtCOLLAPSED(id_bibrec=self.id_bibrec, id_cmtRECORDCOMMENT=self.id,
                         id_user=id_user)
        db.session.add(c)
        db.session.commit()