/**
  * Access the user profile endpoint
  * @since  1.0.0
  * @param  string  $user     Twitter username
  * @return response|wp_error Response or wp_error object
  */
 public function get_user($user = '')
 {
     if ($error = self::app_setup_error()) {
         return $error;
     }
     self::$user = $user ? $user : self::$user;
     if (!self::$user) {
         return new WP_Error('twitterwp_error', __('ERROR: You need to provide a user.'));
     }
     $response = wp_remote_get($this->user_url(), apply_filters('twitterwp_get_tweets', $this->header_args('oauth')));
     if (is_wp_error($response)) {
         return '<strong>ERROR:</strong> ' . $response->get_error_message();
     }
     return $this->return_data($response, $error);
 }