code: func IsProjectWriter(c context.Context, pcfg *svcconfig.ProjectConfig) error {
  	return checkMember(c, pcfg.WriterAuthGroups...)
  }
docs: // IsProjectWriter tests whether the current user belongs to one of the
  // project's declared writer groups.
  //
  // If the user is not a member of any of the groups, a MembershipError will be
  // returned.