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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 zone_compare(timezone):
    '''
    Compares the given timezone with the machine timezone. Mostly useful for
    running state checks.

    Args:
        timezone (str):
            The timezone to compare. This can be in Windows or Unix format. Can
            be any of the values returned by the ``timezone.list`` function

    Returns:
        bool: ``True`` if they match, otherwise ``False``

    Example:

    .. code-block:: bash

        salt '*' timezone.zone_compare 'America/Denver'
    '''
    # if it's one of the key's just use it
    if timezone.lower() in mapper.win_to_unix:
        check_zone = timezone

    elif timezone.lower() in mapper.unix_to_win:
        # if it's one of the values, use the key
        check_zone = mapper.get_win(timezone)

    else:
        # Raise error because it's neither key nor value
        raise CommandExecutionError('Invalid timezone passed: {0}'
                                    ''.format(timezone))

    return get_zone() == mapper.get_unix(check_zone, 'Unknown')