calc in cmd | Python Fiddle

def start():
	print('   Welcome, I\'m your smart calculator!')
	start_question = input('    Would you like to skip the start tips \n     Continue to watch the tips?\n        Enter\'Y\' or \'N\':  ')
	if start_question == 'Y':
		help()
	else:
		wyta()

def help():
	import time
	ts = time.sleep

print('  Hi, I\'m your smart calculator! And i can solve examples with:')
	ts(2)
	print('  \'+\' – Addition;')
	ts(1.3)
	print('  \'-\' – Subtraction;')
	ts(1.3)
	print('  \'*\' – Multiplication;')
	ts(1.3)
	print('  \'/\' – Division;')
	ts(1.3)
	print('  \'**\' – Exponentiation;')
	ts(1.3)
	print('  \'%\' – Interest calculation;')
	ts(1.3)
	print('  \'help\' – Call up the help menu.')
	ts(1.3)
	print('     The quit command works in all menus, which provide the ability to enter anything.')
	ts(2)
	wyta()

# Continue
def wyta():
	import sys
	import math

enter = input('   Indicate what action you want to solve the task: ')
	if enter == '+':
		a = float(input(' Enter the first number: '))
		b = float(input(' Enter the second number: '))
		c = a + b
		print('  Result: ' + str(c))
		choice_to_leave_from_program()

elif enter == '-':
		a = float(input(' Enter the first number: '))
		b = float(input(' Enter the second number: '))
		c = a - b
		print('  Result: ' + str(c))
		choice_to_leave_from_program()

elif enter == '*':
		a = float(input(' Enter the first number: '))
		b = float(input(' Enter the second number: '))
		c = a * b
		print('  Result: ' + str(c))
		choice_to_leave_from_program()
	
	elif enter == '/':
		a = float(input(' Enter the first number: '))
		b = float(input(' Enter the second number: '))
		c = a / b
		print('  Result: ' + str(c))
		choice_to_leave_from_program()

elif enter == 'quit' or 'QUIT' or 'Quit' or 'QUit' or 'QUIt' or 'quiT' or 'qUit' or 'QuiT' or 'quiT':
		sys.exit()

else:
		print('Unknown operation.')
		wyta()

def choice_to_leave_from_program():
	import time
	import sys
	ts = time.sleep

choice = input('Will u try again? Send \'Y\' or \'N\':  ')
	if choice == 'Y':
			print('')
			print('Okay!')
			print('')
			wyta()
	elif choice == 'HELP':
		help()
	else:
		ts(0.4)
		print('Script completion.')
		ts(0.4)
		print('Script completion..')
		ts(0.4)
		print('Script completion...')
		ts(0.4)
		print('   The scripts are complete.\n   Program completed.')
		sys.exit()

while 1 == 1:
	start()

Python Fiddle

Python Cloud IDE