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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 to_query(self):
 """ Iterates over all filters and converts them to an Elastic HTTP API suitable query. Note: each :class:`~es_fluent.filters.Filter` is free to set it's own filter dictionary. ESFluent does not attempt to guard against filters that may clobber one another. If you wish to ensure that filters are isolated, nest them inside of a boolean filter such as :class:`~es_fluent.filters.core.And` or :class:`~es_fluent.filters.core.Or`. """

        query = {}
        for filter_instance in self.filters:
            if filter_instance.is_empty():
                continue
            filter_query = filter_instance.to_query()
            query.update(filter_query)

        return query