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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_key_for_schema_and_document_string(self, schema, request_string):
 # type: (GraphQLSchema, str) -> int """This method returns a unique key given a schema and a request_string"""

        if self.use_consistent_hash:
            schema_id = get_unique_schema_id(schema)
            document_id = get_unique_document_id(request_string)
            return hash((schema_id, document_id))
        return hash((schema, request_string))