code: def test_read_file():
      """Test case for reading GCS"""
  
      from google.cloud import storage
  
      client = storage.Client(
          project="[PROJECT]",
          _http=requests.Session(),
          client_options={"api_endpoint": "http://localhost:9099"},
      )
  
      body = b"1234567"
  
      # Setup the GCS bucket and key
      key_name = "TEST"
      bucket_name = f"gs{int(time.time())}e"
      bucket = client.create_bucket(bucket_name)
  
      blob = bucket.blob(key_name)
      blob.upload_from_string(body)
  
      response = blob.download_as_bytes()
      assert response == body
  
      os.environ[
          "CLOUD_STORAGE_TESTBENCH_ENDPOINT"
      ] = "http://localhost:9099"
  
      content = tf.io.read_file(f"gs://{bucket_name}/{key_name}")
      assert content == body
  
file_path: io/tests/test_gcs.py
imports: import os
  import sys
  import time
  import requests
  import tensorflow
  import tensorflow_io_gcs_filesystem
  import pytest
label_desc: Use image node_id 1 for calling a global function with example usage: test_read_file() without return types