from datetime import datetime
time = datetime.strptime('11:00', '%H:%M')
time2 = datetime.strptime('16:00', '%H:%M')
while True
if time.time() == datetime.now().time().replace(microsecond=0):
pass #Ваша задача на 11:00
elif time2.time() == datetime.now().time().replace(microsecond=0):
pass # Ваша задача на 16:00