async def METHOD_NAME(self):
    path = Path(self.context["path"])
    try:
        import_data = await to_thread(load_reference_file, path)
    except json.decoder.JSONDecodeError as err:
        return await self._set_error(str(err).split("JSONDecodeError: ")[1])
    except OSError as err:
        if "Not a gzipped file" in str(err):
            return await self._set_error("Not a gzipped file")
        return await self._set_error(str(err))
    if errors := check_import_data(import_data, strict=False, verify=True):
        return await self._set_error(errors)
    self.import_data = ReferenceSourceData(**import_data)