def parse_region(region):
    """
    Parse region of type chr1:10-20 or chr1:10-20:+

    Parameters:
    -----------

    region : str
        Region of type chr1:10-20 or chr1:10-20:+.

    Returns
    -------
    groups : tuple
        Tuple of groups from regex e.g. (chr1, 10, 20) or (chr1, 10, 20, +).

    """
    m = R_REGEX_STRAND.search(region)
    if not m:
        m = R_REGEX.search(region)
    if m:
        groups = m.groups()
        return groups
    else:
        return None