code: public function get($id)
      {
          if (!$this->has($id)) {
              throw new NotFoundException(sprintf('%s not found in %s', $id, __CLASS__));
          }
  
          return $this->objects[$id];
      }
docs: Finds an entry of the container by its identifier and returns it.
  
  @param string $id Identifier of the entry to look for.
  
  @throws NotFoundException  No entry was found for this identifier.
  @throws ContainerException Error while retrieving the entry.
  
  @return mixed Entry.