How to use Google Spreadsheet API in Laravel Commands?

Hi,

I'm trying to run Google spread sheet api in my laravel command. I have added the dependency using composer as instructed in tutorial. But it's saying ,

 [Symfony\Component\Debug\Exception\FatalThrowableError]
  Class 'App\Command\Google_Client' not found

Composer :

"require": {
        "php": ">=5.6.4",
        "google/apiclient": "^2.0",
        "laravel/framework": "5.4.*",
        "laravel/tinker": "~1.0"
    },

I have following code in my Test() method of command file.

Link: https://developers.google.com/sheets/api/quickstart/php

Code :

<?php

namespace App\Command;

class MyClass
{
    public static function Test()
    {
        define('APPLICATION_NAME', 'Google Sheets API PHP Quickstart');
        define('CREDENTIALS_PATH', '~/.credentials/sheets.googleapis.com-php-quickstart.json');
        define('CLIENT_SECRET_PATH', 'client_secret.json');
        // If modifying these scopes, delete your previously saved credentials
        // at ~/.credentials/sheets.googleapis.com-php-quickstart.json
        define('SCOPES', implode(' ', array(
          Google_Service_Sheets::SPREADSHEETS_READONLY)
        ));

        if (php_sapi_name() != 'cli') {
          throw new Exception('This application must be run on the command line.');
        }

        /**
         * Returns an authorized API client.
         * @return Google_Client the authorized client object
         */
        function getClient() {
          $client = new Google_Client();
          $client->setApplicationName(APPLICATION_NAME);
          $client->setScopes(SCOPES);
          $client->setAuthConfig(CLIENT_SECRET_PATH);
          $client->setAccessType('offline');

          // Load previously authorized credentials from a file.
          $credentialsPath = expandHomeDirectory(CREDENTIALS_PATH);
          if (file_exists($credentialsPath)) {
            $accessToken = json_decode(file_get_contents($credentialsPath), true);
          } else {
            // Request authorization from the user.
            $authUrl = $client->createAuthUrl();
            printf("Open the following link in your browser:\n%s\n", $authUrl);
            print 'Enter verification code: ';
            $authCode = trim(fgets(STDIN));

            // Exchange authorization code for an access token.
            $accessToken = $client->fetchAccessTokenWithAuthCode($authCode);

            // Store the credentials to disk.
            if(!file_exists(dirname($credentialsPath))) {
              mkdir(dirname($credentialsPath), 0700, true);
            }
            file_put_contents($credentialsPath, json_encode($accessToken));
            printf("Credentials saved to %s\n", $credentialsPath);
          }
          $client->setAccessToken($accessToken);

          // Refresh the token if it's expired.
          if ($client->isAccessTokenExpired()) {
            $client->fetchAccessTokenWithRefreshToken($client->getRefreshToken());
            file_put_contents($credentialsPath, json_encode($client->getAccessToken()));
          }
          return $client;
        }

        /**
         * Expands the home directory alias '~' to the full path.
         * @param string $path the path to expand.
         * @return string the expanded path.
         */
        function expandHomeDirectory($path) {
          $homeDirectory = getenv('HOME');
          if (empty($homeDirectory)) {
            $homeDirectory = getenv('HOMEDRIVE') . getenv('HOMEPATH');
          }
          return str_replace('~', realpath($homeDirectory), $path);
        }

        // Get the API client and construct the service object.
        $client = getClient();
        $service = new Google_Service_Sheets($client);

        // Prints the names and majors of students in a sample spreadsheet:
        // https://docs.google.com/spreadsheets/d/1BxiMVs0XRA5nFMdKvBdBZjgmUUqptlbs74OgvE2upms/edit
        $spreadsheetId = '1BxiMVs0XRA5nFMdKvBdBZjgmUUqptlbs74OgvE2upms';
        $range = 'Class Data!A2:E';
        $response = $service->spreadsheets_values->get($spreadsheetId, $range);
        $values = $response->getValues();

        if (count($values) == 0) {
          print "No data found.\n";
        } else {
          print "Name, Major:\n";
          foreach ($values as $row) {
            // Print columns A and E, which correspond to indices 0 and 4.
            printf("%s, %s\n", $row[0], $row[4]);
          }
        }
    }
}

Do I need to add something else ?

Thanks!