code: func (rule *delegationRule) matchesDelegator(c context.Context, q *RulesQuery) (bool, error) {
  	if rule.addProjectsAsDelegators && q.Delegator.Kind() == identity.Project {
  		return true, nil
  	}
  	allowedDelegators := rule.delegators
  	if rule.addRequestorAsDelegator {
  		allowedDelegators = identityset.Extend(allowedDelegators, q.Requestor)
  	}
  	return allowedDelegators.IsMember(c, q.Delegator)
  }
docs: // matchesDelegator is true if 'q.Delegator' is in 'delegators' set (logically).