Code:

def CtoF(value):
    F = value*(9/5)+32
    return str(value) + "°C is " + str(F) + "°F"
def FtoC(value):
    C = (value-32)*5/9
    return str(value) + "°F is " + str(C) + "°C"

choice = input("1 - Celsius to Fahrenheit\n2 - Fahrenheit to Celsius\nChoose an option: ")

if int(choice) == 1:
    value = input("Enter value in Celsius: ")
    print(CtoF(float(value)))
elif int(choice) == 2:
    value = input("Enter value in Fahreneheit: ")
    print(FtoC(float(value)))