Epoch.py

import time 
from datetime import datetime

tm = time.localtime(1648771200000 / 1000)
s = time.strftime('%Y-%m-%d %H:%M:%S', tm)
print(s)

r = time.strptime("2022-05-01 09:00:00", '%Y-%m-%d %H:%M:%S')
print(r)

mi = time.mktime(r) * 1000
print(mi)