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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(context, command):
    '''Get command help'''
    if command:
        cmd = cli.commands.get(command, None)
        if cmd:
            context.info_name = command
            click.echo(cmd.get_help(context))
        else:
            raise click.ClickException('no command: %s' % command)
    else:
        click.echo(cli.get_help(context))