code: func (f *FakeCloud) InstanceExistsByProviderID(ctx context.Context, providerID string) (bool, error) {
  	f.addCall("instance-exists-by-provider-id")
  	return f.ExistsByProviderID, f.ErrByProviderID
  }
docs: // InstanceExistsByProviderID returns true if the instance with the given provider id still exists and is running.
  // If false is returned with no error, the instance will be immediately deleted by the cloud controller manager.