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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _commands(ctx):
 """Prints a list of commands for shell completion hooks."""

    ctx = ctx.parent
    ctx.show_hidden_subcommands = False
    main = ctx.command

    for subcommand in main.list_commands(ctx):
        cmd = main.get_command(ctx, subcommand)
        if cmd is None:
            continue
        help = cmd.short_help or ""
        click.echo("{}:{}".format(subcommand, help))