def calculate_previous_version(version: str, is_point: bool) -> str:
    """Calculate the previous version to compare to.

    In the case of -rc to final that verison is the previous .0 release,
    (19.3.0 in the case of 20.0.0, for example). for point releases that is
    the last point release. This value will be the same as the input value
    for a poiont release, but different for a major release.
    """
    if '-' in version:
        version = version.split('-')[0]
    if is_point:
        return version
    base = version.split('.')
    if base[1] == '0':
        base[0] = str(int(base[0]) - 1)
        base[1] = '3'
    else:
        base[1] = str(int(base[1]) - 1)
    return '.'.join(base)