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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 delete_one(self, query):
 """ Deletes one document from the collection :param query: dictionary representing the mongo query :return: DeleteResult """

        item = self.find_one(query)
        result = self.table.remove(where(u'_id') == item[u'_id'])

        return DeleteResult(raw_result=result)