def normalizeRealis(realis):
    """
    Normalizes realis values
    """
    realis = realis.lower()
    
    if realis == "webanno.custom.event_":
        return "actual"
        
    elif realis == "generic" or realis == "general":
        return "generic"
    elif realis == "negative" or realis == "negated":
        return "negative"
    
    return realis.lower()