Время, прошедшее с момента запуска операционной системы на python?

Для windows попробуйте:

# ctypes required for using GetTickCount64() 
import ctypes 
  
# getting the library in which GetTickCount64() resides 
lib = ctypes.windll.kernel32 
  
# calling the function and storing the return value 
t = lib.GetTickCount64() 
  
# since the time is in milliseconds i.e. 1000 * seconds 
# therefore truncating the value 
t = int(str(t)[:-3]) 
  
# extracting hours, minutes, seconds & days from t 
# variable (which stores total time in seconds) 
mins, sec = divmod(t, 60) 
hour, mins = divmod(mins, 60) 
days, hour = divmod(hour, 24) 
  
# formatting the time in readable form 
# (format = x days, HH:MM:SS) 
print(f"{days} days, {hour:02}:{mins:02}:{sec:02}")

Для unix:

import os 
  
# sending the uptime command as an arguement to popen() 
# and saving the returned result (after truncating the trailing \n) 
t = os.popen('uptime -p').read()[:-1] 
  
print(t)

Выводит:

up 15 minutes