Need to sum up HHMMS AM/PM DD/MM/YYYY and a HH:MM:SS.

[deanhystad]

If you are measuring your runtime in seconds it might make more sense using datetime.fromtimestamp()

from datetime import datetime

now = datetime.now().timestamp()
runtime = 1 * 3600 + 22 * 60 + 14  # 1:22:14 seconds

print(datetime.fromtimestamp(now))
print(datetime.fromtimestamp(now + runtime))

Output:
2023-01-04 14:52:30.891579
2023-01-04 16:14:44.891579

If your runtime is a HH:MM:SS string, Yoriz's solution is a better choice.