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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_request_query(self):
 """Checks the request for known catalog indexes and converts the values to fit the type of the catalog index. :param catalog: The catalog to build the query for :type catalog: ZCatalog :returns: Catalog query :rtype: dict """

        query = {}

        # only known indexes get observed
        indexes = self.catalog.get_indexes()

        for index in indexes:
            # Check if the request contains a parameter named like the index
            value = req.get(index)
            # No value found, continue
            if value is None:
                continue
            # Convert the found value to format understandable by the index
            index_value = self.catalog.to_index_value(value, index)
            # Conversion returned None, continue
            if index_value is None:
                continue
            # Append the found value to the query
            query[index] = index_value

        return query