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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 _create_fulltext_query(self):
 """Support the json-server fulltext search with a broad LIKE filter."""

        filter_by = []

        if 'q' in request.args:
            columns = flat_model(model_tree(self.__class__.__name__, self.model_cls))
            for q in request.args.getlist('q'):
                filter_by += ['{col}::like::%{q}%'.format(col=col, q=q) for col in columns]

        return filter_by