How do I convert seconds to hours, minutes and seconds?
You can use datetime.timedelta function:
>>> import datetime
>>> str(datetime.timedelta(seconds=666))
'0:11:06'
By using the divmod() function, which does only a single division to produce both the quotient and the remainder, you can have the result very quickly with only two mathematical operations:
m, s = divmod(seconds, 60)
h, m = divmod(m, 60)
And then use string formatting to convert the result into your desired output:
print('{:d}:{:02d}:{:02d}'.format(h, m, s)) # Python 3
print(f'{h:d}:{m:02d}:{s:02d}') # Python 3.6+