docs: def item_details(item_id, lang="en"):
      """This resource returns a details about a single item.
  
      :param item_id: The item to query for.
      :param lang: The language to display the texts in.
  
      The response is an object with at least the following properties. Note that
      the availability of some properties depends on the type of the item.
  
      item_id (number):
          The item id.
  
      name (string):
          The name of the item.
  
      description (string):
          The item description.
  
      type (string):
          The item type.
  
      level (integer):
          The required level.
  
      rarity (string):
          The rarity. On of ``Junk``, ``Basic``, ``Fine``, ``Masterwork``,
          ``Rare``, ``Exotic``, ``Ascended`` or ``Legendary``.
  
      vendor_value (integer):
          The value in coins when selling to a vendor.
  
      icon_file_id (string):
          The icon file id to be used with the render service.
  
      icon_file_signature (string):
          The icon file signature to be used with the render service.
  
      game_types (list):
          The game types where the item is usable.
          Currently known game types are: ``Activity``, ``Dungeon``, ``Pve``,
          ``Pvp``, ``PvpLobby`` and ``WvW``
  
      flags (list):
          Additional item flags.
          Currently known item flags are: ``AccountBound``, ``HideSuffix``,
          ``NoMysticForge``, ``NoSalvage``, ``NoSell``, ``NotUpgradeable``,
          ``NoUnderwater``, ``SoulbindOnAcquire``, ``SoulBindOnUse`` and
          ``Unique``
  
      restrictions (list):
          Race restrictions: ``Asura``, ``Charr``, ``Human``, ``Norn`` and
          ``Sylvari``.
  
      Each item type has an `additional key`_ with information specific to that
      item type.
  
      .. _additional key: item-properties.html
  
      """
      params = {"item_id": item_id, "lang": lang}
      cache_name = "item_details.%(item_id)s.%(lang)s.json" % params
      return get_cached("item_details.json", cache_name, params=params)