code: def bucket(self, bucket_name, user_project=None):
          
          return Bucket(client=self, name=bucket_name, user_project=user_project)
docs: Factory constructor for bucket object.
  
          .. note::
            This will not make an HTTP request; it simply instantiates
            a bucket object owned by this client.
  
          :type bucket_name: str
          :param bucket_name: The name of the bucket to be instantiated.
  
          :type user_project: str
          :param user_project: (Optional) the project ID to be billed for API
                               requests made via the bucket.
  
          :rtype: :class:`google.cloud.storage.bucket.Bucket`
          :returns: The bucket object created.