def METHOD_NAME(example_command_with_aliases: Command):
    """Test that `command_name in registry` works."""
    registry = CommandRegistry()
    command = example_command_with_aliases
    assert command.name not in registry
    assert "nonexistent_command" not in registry
    registry.register(command)
    assert command.name in registry
    assert "nonexistent_command" not in registry
    for alias in command.aliases:
        assert alias in registry