How to use the azure-storage-file.azure.storage.file._constants.X_MS_VERSION function in azure-storage-file

def __init__(self, account_name, account_key):
        '''
        :param str account_name:
            The storage account name used to generate the shared access signatures.
        :param str account_key:
            The access key to generate the shares access signatures.
        '''
        super(FileSharedAccessSignature, self).__init__(account_name, account_key, x_ms_version=X_MS_VERSION)

super(FileService, self).__init__(service_params)

        if self.account_name == DEV_ACCOUNT_NAME:
            raise ValueError(_ERROR_EMULATOR_DOES_NOT_SUPPORT_FILES)

        if self.account_key:
            self.authentication = _StorageSharedKeyAuthentication(
                self.account_name,
                self.account_key,
            )
        elif self.sas_token:
            self.authentication = _StorageSASAuthentication(self.sas_token)
        else:
            raise ValueError(_ERROR_STORAGE_MISSING_INFO)
        self._X_MS_VERSION = X_MS_VERSION
        self._update_user_agent_string(package_version)