input: Write a python function to generate the n-th Fibonacci number.
  assert FibonacciGenerator(10) == 34
  assert FibonacciGenerator(1) == 1
  assert FibonacciGenerator(0) == 0
  assert FibonacciGenerator(7) == 8
output: def FibonacciGenerator(n):
      if n == 0:
          return 0
      elif n == 1:
          return 1
      else:
          a, b = 0, 1
          for _ in range(2, n+1):
              a, b = b, a + b
          return b