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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_query(self, key_val={}):
 """ Add an es_dsl query object to the es_dsl Search object :param key_val: a key-value pair(dict) containing the query to be added to the search object :returns: self, which allows the method to be chainable with the other methods """


        q = Q("match", **key_val)
        self.search = self.search.query(q)
        return self