input: Write a function to print the Fibonacci series up to a given number. The function should take an integer `n` as input and print all Fibonacci numbers up to `n`.
  assert fibonacci_series(10) == "0 1 1 2 3 5 8"
  assert fibonacci_series(1) == "0"
  assert fibonacci_series(2) == "0 1"
  assert fibonacci_series(0) == ""
  assert fibonacci_series(-5) == "Incorrect input"
output: def fibonacci_series(n):
      if n < 0:
          return "Incorrect input"
      if n == 0:
          return ""
      if n == 1:
          return "0"
      fib_sequence = [0, 1]
      while fib_sequence[-1] + fib_sequence[-2] <= n:
          fib_sequence.append(fib_sequence[-1] + fib_sequence[-2])
      return ' '.join(map(str, fib_sequence))