def __enter__()

in src/guclimate/requests/transform.py [0:0]


    def __enter__(self):
        file_types = self.download.get_file_types()

        if len(file_types) > 1:
            raise ValueError(
                f"Multiple file types found in downloaded files: {
                    ', '.join(file_types)}"
            )

        if file_types[0] != ".grib":
            raise ValueError(
                f"Downloading '{file_types[0]}' is not currently supported"
            )

        return self