input: def exponential_series(x: float, n: int) -> float:
      """
      Calculate the sum of the exponential series from 0 to n of x.
  
      >>> exponential_series(2, 3)
      15.0
      >>> exponential_series(1, 10)
      11.0
      """
      sum = 0
      for i in range(n + 1):
          sum += x ** i
      return sum
output:     sum = 0
      for i in range(n + 1):
          sum += x ** i
      return sum