code: public function retrieve($httpMethod, $uri)
      {
          $route = array($httpMethod, $uri);
  
          $routes = array_map(function ($route) {
              return array($route[0], $route[1]);
          }, $this->routes);
  
          $key = array_search($route, $routes);
  
          return $key !== false ? $this->routes[$key] : null;
      }
docs: Returns a specific route based on the specified HTTP method and URI.
  
  @param  string $httpMethod
  @param  string $uri
  @return array|null