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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 get_relation_count_query_for_self_join(self, query, parent):
 """ Add the constraints for a relationship count query on the same table. :type query: eloquent.orm.Builder :type parent: eloquent.orm.Builder :rtype: eloquent.orm.Builder """

        query.select(QueryExpression('COUNT(*)'))

        table_prefix = self._query.get_query().get_connection().get_table_prefix()

        hash_ = self.get_relation_count_hash()
        query.from_('%s AS %s%s' % (self._table, table_prefix, hash_))

        key = self.wrap(self.get_qualified_parent_key_name())

        return query.where('%s.%s' % (hash_, self._foreign_key), '=', QueryExpression(key))