def get_version_name(version_const):
    """\
    Returns the version name.

    For version 1 .. 40 it returns the version as integer, for Micro QR Codes
    it returns a string like ``M1`` etc.

    :raises: VersionError: In case the `version_constant` is unknown.
    """
    if 0 < version_const < 41:
        return version_const
    for name, v in consts.MICRO_VERSION_MAPPING.items():
        if v == version_const:
            return name
    raise VersionError('Unknown version constant "{0}"'.format(version_const))
\
    Returns the version name.

    For version 1 .. 40 it returns the version as integer, for Micro QR Codes
    it returns a string like ``M1`` etc.

    :raises: VersionError: In case the `version_constant` is unknown.