Add or Subtract two Duration in Python

def main():
	"""
	Subtracts two time values.
	"""

	time_a = input("Enter time (hh:mm:ss): ")
	time_b = input("Subtract   (hh:mm:ss): ")

	sec_a = get_total_seconds(time_a)
	sec_b = get_total_seconds(time_b)

	sec_diff = abs(sec_a - sec_b)
	hr, remainder = divmod(sec_diff, 3600)
	mn, sc = divmod(remainder, 60)

	print(f"{hr:02d}:{mn:02d}:{sc:02d}")


def get_total_seconds(time_str: str) -> int:
	units = time_str.split(":")
	if len(units) != 3:
		raise ValueError("Invalid format")

	hr, mn, sc = map(int, units)
	return hr * 3600 + mn * 60 + sc


if __name__ == "__main__":
	main()

def main():
	"""
	Adds two time values.
	"""

	time_a = input("Enter time (hh:mm:ss): ")
	time_b = input("Subtract   (hh:mm:ss): ")

	sec_a = get_total_seconds(time_a)
	sec_b = get_total_seconds(time_b)

	total_seconds = sec_a + sec_b
	hours = total_seconds // 3600
	total_seconds %= 3600
	minutes = total_seconds // 60
	seconds = total_seconds % 60

	print(f"{hours:02d}:{minutes:02d}:{seconds:02d}")


def get_total_seconds(time_str: str):
	units = time_str.split(":")
	if len(units) != 3:
		raise ValueError("Invalid format")

	hr = int(units[0])
	mn = int(units[1])
	sc = int(units[2])
	return hr * 3600 + mn * 60 + sc


if __name__ == "__main__":
	main()