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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 help(ctx, command):
 """Display help for a command."""

    command = ' '.join(command)
    if not command:
        click.echo(cli.get_help(ctx))
        return

    cmd = cli.get_command(ctx, command)
    if cmd:
        click.echo(cmd.get_help(ctx))
    else:
        click.echo(cli.get_help(ctx))