input: Write a function to print the Fibonacci series up to n numbers where n is a user input.
  assert fibonacci_series(10)
  assert fibonacci_series(5)
  assert fibonacci_series(0)
  assert fibonacci_series(1)
  assert fibonacci_series(2)
output: def fibonacci_series(n):
      if n <= 0:
          return []
      elif n == 1:
          return [0]
      elif n == 2:
          return [0, 1]
      
      series = [0, 1]
      for i in range(2, n):
          series.append(series[-1] + series[-2])
      return series