how to make a calculator using idle

1def calculate():
2    operation = input('''
3Please type in the math operation you would like to complete:
4+ for addition
5- for subtraction
6* for multiplication
7/ for division
8''')
9
10    number_1 = int(input('Please enter the first number: '))
11    number_2 = int(input('Please enter the second number: '))
12
13    if operation == '+':
14        print('{} + {} = '.format(number_1, number_2))
15        print(number_1 + number_2)
16
17    elif operation == '-':
18        print('{} - {} = '.format(number_1, number_2))
19        print(number_1 - number_2)
20
21    elif operation == '*':
22        print('{} * {} = '.format(number_1, number_2))
23        print(number_1 * number_2)
24
25    elif operation == '/':
26        print('{} / {} = '.format(number_1, number_2))
27        print(number_1 / number_2)
28
29    else:
30        print('You have not typed a valid operator, please run the program again.')
31
32    # Add again() function to calculate() function
33    again()
34
35def again():
36    calc_again = input('''
37Do you want to calculate again?
38Please type Y for YES or N for NO.
39''')
40
41    if calc_again.upper() == 'Y':
42        calculate()
43    elif calc_again.upper() == 'N':
44        print('See you later.')
45    else:
46        again()
47
48calculate()