input: Write a function to demonstrate the concept of recursion in Python by defining a recursive function to calculate the factorial of a given number and then print the factorial of number 5.
  
  def factorial(n):
     if n == 1:
        return 1
     else:
        return n * factorial(n - 1)
  
  result = factorial(5)
  print("Factorial of 5 is ", result)
  
  assert result == 120
  print("Factorial of 5 is 120")
output: def factorial(n):
     if n == 1:
        return 1
     else:
        return n * factorial(n - 1)