Parse multiple versions as read from disk. The versions value may be any
    one of:
        - a single version string ('>0.12.1')
        - a single string specifying multiple comma-separated versions
            ('>0.11.1,<=0.12.2')
        - an array of single-version strings (['>0.11.1', '<=0.12.2'])

    Regardless, this will return a list of VersionSpecifiers

def _parse_versions(versions):
    """Parse multiple versions as read from disk. The versions value may be any
    one of:
        - a single version string ('>0.12.1')
        - a single string specifying multiple comma-separated versions
            ('>0.11.1,<=0.12.2')
        - an array of single-version strings (['>0.11.1', '<=0.12.2'])

    Regardless, this will return a list of VersionSpecifiers
    """
    if isinstance(versions, compat.basestring):
        versions = versions.split(',')
    return [VersionSpecifier.from_version_string(v) for v in versions]