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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 add_clause(self, clause):
 """Add a new clause to the existing query. :param clause: The clause to add :type clause: MongoClause :return: None """

        if clause.query_loc == MongoClause.LOC_MAIN:
            self._main.append(clause)
        elif clause.query_loc == MongoClause.LOC_MAIN2:
            self._main2.append(clause)
        elif clause.query_loc == MongoClause.LOC_WHERE:
            self._where.append(clause)
        else:
            raise RuntimeError('bad clause location: {}'.format(clause.query_loc))