langchain/tools/openapi/utils/openapi_utils.py/OpenAPISpec/get_request_body_for_operation
class OpenAPISpec:    def get_request_body_for_operation(
        self, operation: Operation
    ) -> Optional[RequestBody]:
        """Get the request body for a given operation."""
        request_body = operation.requestBody
        if isinstance(request_body, Reference):
            request_body = self._get_root_referenced_request_body(request_body)
        return request_body