code: def check_bucket(bucket_name, message):
      """Check if GCS bucket path is valid."""
      while not bucket_name.startswith("gs://"):
          print(
              f"Path {bucket_name} is not a valid GCS bucket. "
              "Bucket paths must start with gs://."
          )
          bucket_name = input(message)
  
      while True:
          try:
              name = bucket_name.split("gs://")[1]
              if "/" in name:
                  name = name.split("/")[0]
              storage.Client().get_bucket(name)
              break
  
          except:  # pylint: disable=bare-except
              print(
                  f"Bucket {bucket_name} doesn't exist or can't be accessed."
              )
              bucket_name = input(message)
  
      return bucket_name
  
imports: import datetime
  import os
  import subprocess
  from absl import app
  from absl import flags
  from google.cloud import storage
label_desc: Use image node_id 5 for calling a global function with example usage: check_bucket(bucket_name, message) and returns: bucket_name