If it is a list of tuples of integers you could run this:
l = [(1210, 1229), (1935, 2000), (1536, 1608), (1043, 1120), (1817, 1922), (900, 1023), (1632, 1759)]
result = []
for x in l:
time_one = f'{x[0]:0>4}'
time_two = f'{x[1]:0>4}'
split_time_one = time_one[:2] + ':' + time_one[2:]
split_time_two = time_two[:2] + ':' + time_two[2:]
result.append((split_time_one, split_time_two,))
print(result)
# [('12:10', '12:29'), ('19:35', '20:00'), ('15:36', '16:08'), ('10:43', '11:20'), ('18:17', '19:22'), ('09:00', '10:23'), ('16:32', '17:59')]
Note Python 3.6 or higher is required for this to function.
t = datetime.time(n //100, n % 100), you can uset.strftime("%H:%M")to get a properly formatted time string.