ArcGIS Pro Field Calculator time.sleep

[SUBHADIPDATTA]

I want to add numbering in a column but with an interval of time to avoid the last edited date. 

from time import sleep
rec=0
def sqn():
global rec
pStart = 1
pInterval = 1
sleep(15)
if (rec == 0):
rec = pStart
else:
rec = rec + pInterval
return rec

I tried with a time sleep of 15 sec but it is not working. It is not reflecting the 15-sec interval on the last edited date column.

Any code to use python field calculator with an interval of time?