import re


def parse_openssh_version(version_string):
    """Parse the version output of ssh -V and return version numbers that can be compared"""

    parsed_result = re.match(
        r"^.*openssh_(?P<version>[0-9.]+)(p?[0-9]+)[^0-9]*.*$", version_string.lower()
    )
    if parsed_result is not None:
        version = parsed_result.group("version").strip()
    else:
        version = None

    return version