Parse version string to a VersionInfo instance.

    :param version: version string
    :return: a :class:`VersionInfo` instance
    :rtype: :class:`VersionInfo`

    >>> import semver
    >>> version_info = semver.parse_version_info("3.4.5-pre.2+build.4")
    >>> version_info.major
    3
    >>> version_info.minor
    4
    >>> version_info.patch
    5
    >>> version_info.prerelease
    'pre.2'
    >>> version_info.build
    'build.4'

def parse_version_info(version):
    """Parse version string to a VersionInfo instance.

    :param version: version string
    :return: a :class:`VersionInfo` instance
    :rtype: :class:`VersionInfo`

    >>> import semver
    >>> version_info = semver.parse_version_info("3.4.5-pre.2+build.4")
    >>> version_info.major
    3
    >>> version_info.minor
    4
    >>> version_info.patch
    5
    >>> version_info.prerelease
    'pre.2'
    >>> version_info.build
    'build.4'
    """
    parts = parse(version)
    version_info = VersionInfo(
            parts['major'], parts['minor'], parts['patch'],
            parts['prerelease'], parts['build'])

    return version_info