langchain/tools/openapi/utils/api_models.py/APIOperation/from_openapi_url
class APIOperation:    def from_openapi_url(
        cls,
        spec_url: str,
        path: str,
        method: str,
    ) -> "APIOperation":
        """Create an APIOperation from an OpenAPI URL."""
        spec = OpenAPISpec.from_url(spec_url)
        return cls.from_openapi_spec(spec, path, method)