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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def skin_details(skin_id, lang="en"):
 """This resource returns details about a single skin. :param skin_id: The skin 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 item the skin applies to. skin_id (number):
 The skin id. name (string):
 The name of the skin. type (string):
 The type of item the skin applies to. One of ``Armor``, ``Back`` or ``Weapon``. flags (list):
 Skin flags. Currently known skin flags are ``ShowInWardrobe``, ``HideIfLocked`` and ``NoCost``. restrictions (list):
 Race restrictions: ``Asura``, ``Charr``, ``Human``, ``Norn`` and ``Sylvari``. 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. """

    params = {"skin_id": skin_id, "lang": lang}
    cache_name = "skin_details.%(skin_id)s.%(lang)s.json" % params
    return get_cached("skin_details.json", cache_name, params=params)