code: public function findOauthClientById($user_id, $client_id)
      {
          list($response) = $this->findOauthClientByIdWithHttpInfo($user_id, $client_id);
          return $response;
      }
docs: Operation findOauthClientById
  
  
  
  @param string $user_id ID of user to retrieve (required)
  @param string $client_id ID of Oauth client to retrieve (required)
  @return \ProcessMaker\PMIO\Model\OauthClientItem
  @throws \ProcessMaker\PMIO\ApiException on non-2xx response