Time dilation calculator in python

timedi.py

import re

def main():
	running = True

	while running:

		print('Enter a speed in m/s or as a fraction of the speed of light.')
		print('m/s in the format: x m/s, fraction in the format 0.x')

		speed = input()
		# regexes to check what format the input is in
		fraction = r'0\.[0-9]+'
		raw_speed = r'[0-9]+[ ]*m/s'
		is_fraction = re.search(fraction, speed)
		is_raw_speed = re.search(raw_speed, speed)

		# if the input is in a correct format
		if is_fraction or is_raw_speed:

			if is_raw_speed:
				# remove m/s part of the string and any spaces
				speed = float(speed.split('m/s')[0].strip(' '))
				input_format = 'r'
			elif is_fraction:
				# convert fraction as a string to float
				speed = float(speed)
				input_format = 'f'
			# use calc_time_dilation to calculate the amount of time dilation
			# between an obe
			dilation = calc_time_dilation(speed, speed_format=input_format)
			
			print('\nTime dilation relative to stationary observer: {0}\n'.format(dilation))
			print('Press q to quit or any other key to enter another value')
			
			again = input()
			
			if again.lower() == 'q':
				running = False
		else:
			print('Invalid format')

def calc_time_dilation(speed, speed_format='r'):
	# speed of light 
	c = 299792458 
	
	# if the format is a fraction, the speed of light is multiplied
	# by the fraction to get the speed in m/s
	if speed_format == 'f':
		speed = c * speed
	elif speed_format == 'r':
		if speed > c:
			raise ValueError("Speed is greater than that of light")
	else:
		raise ValueError("Speed format must be a string r or f -- raw speed or fraction")
	

	ratio_to_c = (speed ** 2) / (c ** 2)
	dilation = 1 / ((1 - ratio_to_c) ** 0.5)
	return dilation

if __name__ == '__main__':
	main()

Does this calculate how much more time passed for the object? And Is it in seconds

I wrote this 8 years ago so not 100% sure but I think it just gives the ratio of time in the other frame to time in the observers frame, i.e if this result was 0.5, for each 1s that the observer experienced, 0.5s would elapse in the other frame