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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 cli(ctx, packages, all, list, force, platform):
 """Install packages."""


    if packages:
        for package in packages:
            Installer(package, platform, force).install()
    elif all:  # pragma: no cover
        packages = Resources(platform).packages
        for package in packages:
            Installer(package, platform, force).install()
    elif list:
        Resources(platform).list_packages(installed=True, notinstalled=True)
    else:
        click.secho(ctx.get_help())