code: def fibonacci(n):
      assert n > 0
      a, b = 0, 1
      for _ in range(n - 1):
          a, b = b, a + b
      return b
  
imports: import ray
  from ray import workflow
  import requests
label_desc: Use image node_id 1 for calling a global function with example usage: fibonacci(n) and returns: b