Why am I getting NameError name _all_timezones_unchecked' is not defined

[AgusBudianto]

I defined the following local time function get datetime:

def get_sysdate():

    jkt_tz = pytz.timezone('Asia/Jakarta')

    sysdate = datetime.now(jkt_tz).strftime('%Y-%m-%d %H:%M:%S')

    return sysdate

spark.udf.register("get_sysdate", get_sysdate)

But sometimes I get the error "_all_timezones_unchecked' is not defined," and the next run works fine.