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      "[Python para Desenvolvedores](http://ricardoduarte.github.io/python-para-desenvolvedores/#conteudo)\n",
      "===================================\n",
      "2ª edi\u00e7\u00e3o, revisada e ampliada\n",
      "-----------------------------------\n",
      "\n",
      "Cap\u00edtulo 24: Decoradores de classe\n",
      "=============================\n",
      "_____________________________\n",
      "A partir da vers\u00e3o 2.6, os decoradores podem ser aplicados em classes.\n",
      "\n",
      "Exemplo:"
     ]
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     "input": [
      "import time\n",
      "\n",
      "def logger(cls):\n",
      "    \"\"\"\n",
      "    Fun\u00e7\u00e3o decoradora de classes\n",
      "    \"\"\"\n",
      "\n",
      "    class Logged(cls):\n",
      "        \"\"\"\n",
      "        Classe derivada que mostra os par\u00e2metros de inicializa\u00e7\u00e3o\n",
      "        \"\"\"\n",
      "\n",
      "        def __init__(self, *args, **kargs):\n",
      "\n",
      "            print 'Hora:', time.asctime()\n",
      "            print 'Classe:', repr(cls)\n",
      "            print 'args:', args\n",
      "            print 'kargs:', kargs\n",
      "            \n",
      "            # Executa a inicializa\u00e7\u00e3o da classe antiga\n",
      "            cls.__init__(self, *args, **kargs)\n",
      "\n",
      "    # Retorna a nova classe\n",
      "    return Logged\n",
      "\n",
      "\n",
      "@logger\n",
      "class Musica(object):\n",
      "\n",
      "    def __init__(self, nome, artista, album):\n",
      "\n",
      "        self.nome = nome\n",
      "        self.artista = artista\n",
      "        self.album = album\n",
      "\n",
      "\n",
      "m = Musica('Hand of Doom', 'Black Sabbath', album='Paranoid')"
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       "text": [
        "Hora: Tue Jul 30 13:40:50 2013\n",
        "Classe: <class '__main__.Musica'>\n",
        "args: ('Hand of Doom', 'Black Sabbath')\n",
        "kargs: {'album': 'Paranoid'}\n"
       ]
      }
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      "Com isso, o decorador mudou o comportamento da classe."
     ]
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