input: Write a function to calculate the Fibonacci numbers up to a given number. If the given number is 0, return 0. If the given number is 1, return 1. For any other number, return the sum of the previous two Fibonacci numbers.
  def Fibonacci(n): 
  	if n==0: 
  		return 0
  	if n==1: 
  		return 1
  	else: 
  		return Fibonacci(n-1)+Fibonacci(n-2)
  
  assert Fibonacci(0)==0
  assert Fibonacci(1)==1
  assert Fibonacci(2)==1
  assert Fibonacci(5)==5
  assert Fibonacci(10)==55
output: def Fibonacci(n): 
  	if n==0: 
  		return 0
  	if n==1: 
  		return 1
  	else: 
  		return Fibonacci(n-1)+Fibonacci(n-2)