title: Access google cloud storage bucket from other project using python
body: <p>lets suppose I have google cloud storage bucket in project X and want to upload object in the bucket which is in project X from Code(Python) which is deployed on project Y.
  Both project X and Y are under same credentials(login id). </p>
  
  <p>Is it achievable using OAuth2.0 or any other suggestion? 
  I have tried using <strong>Service Account,AppAssertionCredentials &amp; OAuth2DecoratorFromClientSecrets</strong> but failed.</p>
  
  <pre><code>credentials = GoogleCredentials.get_application_default()
  service = discovery.build('storage', 'v1', credentials=credentials)
  req = service.objects().insert(
              bucket=bucket_name,
              name=fileName,
              media_body=media)   
  </code></pre>