input: 
  def fibonacci(n: int) -> List[int]:
      """
      Generate a Fibonacci series up to the given number.
      >>> fibonacci(0)
      []
      >>> fibonacci(1)
      [0]
      >>> fibonacci(2)
      [0, 1]
      >>> fibonacci(7)
      [0, 1, 1, 2, 3, 5, 8]
      """
      series = []
      a, b = 0, 1
      while a <= n:
          series.append(a)
          a, b = b, a + b
      return series
  
output:     series = []
      a, b = 0, 1
      while a <= n:
          series.append(a)
          a, b = b, a + b
      return series