def checkversion(version):
    """Checks foliadocserve version, returns 1 if the document is newer than the library, -1 if it is older, 0 if it is equal"""
    try:
        for refversion, responseversion in zip([int(x) for x in REQUIREFOLIADOCSERVE.split('.')], [int(x) for x in version.split('.')]):
            if responseversion > refversion:
                return 1 #response is newer than library
            elif responseversion < refversion:
                return -1 #response is older than library
        return 0 #versions are equal
    except ValueError:
        raise ValueError("Unable to parse version, invalid syntax")