Extra links supported for operators coming from third-party packages:

airflow.serialization.serialized_objects.BUILTIN_OPERATOR_EXTRA_LINKS

airflow/cli/cli_parser.py
help='Export all pools',
        func=lazy_load_command('airflow.cli.commands.pool_command.pool_export'),
        args=(
            ARG_POOL_EXPORT,
            ARG_OUTPUT,
        ),
    ),
)
VARIABLES_COMMANDS = (
    ActionCommand(
        name='list',
        help='List variables',
        func=lazy_load_command('airflow.cli.commands.variable_command.variables_list'),
        args=(ARG_OUTPUT,),
    ),
    ActionCommand(
        name='get',
        help='Get variable',
        func=lazy_load_command('airflow.cli.commands.variable_command.variables_get'),
        args=(ARG_VAR, ARG_JSON, ARG_DEFAULT),
    ),
    ActionCommand(
        name='set',
        help='Set variable',
        func=lazy_load_command('airflow.cli.commands.variable_command.variables_set'),
        args=(ARG_VAR, ARG_VAR_VALUE, ARG_JSON),
    ),
    ActionCommand(
        name='delete',
        help='Delete variable',