code: func (c *controller) ensureLease() (*coordv1beta1.Lease, bool, error) {
  	lease, err := c.leaseClient.Get(c.holderIdentity, metav1.GetOptions{})
  	if apierrors.IsNotFound(err) {
  		// lease does not exist, create it
  		lease, err := c.leaseClient.Create(c.newLease(nil))
  		if err != nil {
  			return nil, false, err
  		}
  		return lease, true, nil
  	} else if err != nil {
  		// unexpected error getting lease
  		return nil, false, err
  	}
  	// lease already existed
  	return lease, false, nil
  }
docs: // ensureLease creates the lease if it does not exist. Returns the lease and
  // a bool (true if this call created the lease), or any error that occurs.