input: Write a function to convert degrees Fahrenheit to degrees Celsius. The function should take a single parameter representing the temperature in Fahrenheit and return the equivalent temperature in Celsius.
  assert FahrenheitToCelsius(32.0)==0.0
  assert FahrenheitToCelsius(212.0)==100.0
  assert FahrenheitToCelsius(-40.0)==-40.0
  assert FahrenheitToCelsius(98.6)==37.0
  assert FahrenheitToCelsius(50.0)==10.0
output: def FahrenheitToCelsius(fahrenheit):
      return (fahrenheit - 32) * 5 / 9