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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 _uninstall(action='remove', name=None, pkgs=None, **kwargs):
    '''
    remove and purge do identical things but with different pacman commands,
    this function performs the common logic.
    '''
    try:
        pkg_params = __salt__['pkg_resource.parse_targets'](name, pkgs)[0]
    except MinionError as exc:
        raise CommandExecutionError(exc)

    old = list_pkgs()
    targets = [x for x in pkg_params if x in old]
    if not targets:
        return {}

    remove_arg = '-Rsc' if action == 'purge' else '-R'

    cmd = []
    if salt.utils.systemd.has_scope(__context__) \
            and __salt__['config.get']('systemd.scope', True):
        cmd.extend(['systemd-run', '--scope'])
    cmd.extend(['pacman', remove_arg, '--noprogressbar', '--noconfirm'])
    cmd.extend(targets)

    if 'root' in kwargs:
        cmd.extend(('-r', kwargs['root']))

    out = __salt__['cmd.run_all'](
        cmd,
        output_loglevel='trace',
        python_shell=False
    )

    if out['retcode'] != 0 and out['stderr']:
        errors = [out['stderr']]
    else:
        errors = []

    __context__.pop('pkg.list_pkgs', None)
    new = list_pkgs()
    ret = salt.utils.data.compare_dicts(old, new)

    if errors:
        raise CommandExecutionError(
            'Problem encountered removing package(s)',
            info={'errors': errors, 'changes': ret}
        )

    return ret