GCP：在本地计算机中使用服务帐户下载Blob对象

Question

import os
os.environ["GOOGLE_APPLICATION_CREDENTIALS"] = "path/to/service_account.json"

def download_blob(bucket_name, source_blob_name,destination_file_name):
    from google.cloud import storage
    storage_client = storage.Client()
    bucket = storage_client.get_bucket(bucket_name)
    blob = bucket.blob(source_blob_name)
    blob.download_to_filename(destination_file_name)
    print('Blob {} downloaded to {}.'.format(source_blob_name,destination_file_name))

  

错误：引发exceptions.from_http_response（响应）   google.api_core.exceptions.Forbidden：403 GET   https://www.googleapis.com/storage/v1/b/test_role?projection=noAcl：    nameofserviceaccount @ projectid .iam.gserviceaccount.com没有storage.buckets.get访问 bucketname 。

服务帐户已获得项目所有者的许可。