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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 3: Controle de fluxo\n",
      "=============================\n",
      "_____________________________\n",
      "\u00c9 muito comum em um programa que certos conjuntos de instru\u00e7\u00f5es sejam executados de forma condicional, em casos como validar entradas de dados, por exemplo.\n",
      "\n",
      "Sintaxe:\n",
      "\n",
      "    if <condi\u00e7\u00e3o>:\n",
      "        <bloco de c\u00f3digo>\n",
      "    elif <condi\u00e7\u00e3o>:\n",
      "        <bloco de c\u00f3digo>\n",
      "    elif <condi\u00e7\u00e3o>:\n",
      "        <bloco de c\u00f3digo>\n",
      "    else:\n",
      "        <bloco de c\u00f3digo>\n",
      "\n",
      "Na qual:\n",
      "\n",
      "+ `<condi\u00e7\u00e3o>`: senten\u00e7a que possa ser avaliada como verdadeira ou falsa.\n",
      "+ `<bloco de c\u00f3digo>`: sequ\u00eancia de linhas de comando.\n",
      "+ As clausulas `elif` e `else` s\u00e3o opcionais e podem existir v\u00e1rios `elifs` para o mesmo `if`, por\u00e9m apenas um else ao final.\n",
      "+ Par\u00eanteses s\u00f3 s\u00e3o necess\u00e1rios para evitar ambiguidades.\n",
      "\n",
      "Exemplo:"
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      "temp = 23 # valor de temperatura usado para teste\n",
      "\n",
      "if temp < 0:\n",
      "    print 'Congelando...'\n",
      "elif 0 <= temp <= 20:\n",
      "    print 'Frio'\n",
      "elif 21 <= temp <= 25:\n",
      "    print 'Normal'\n",
      "elif 26 <= temp <= 35:\n",
      "    print 'Quente'\n",
      "else:\n",
      "    print 'Muito quente!'"
     ],
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       "text": [
        "Normal\n"
       ]
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     "source": [
      "Imagine que no programa acima, `23` \u00e9 a temperatura que foi lida de algum sensor ou entrada manualmente pelo usu\u00e1rio e `Normal` \u00e9 a resposta do programa.\n",
      "\n",
      "Se o bloco de c\u00f3digo for composto de apenas uma linha, ele pode ser escrito ap\u00f3s os dois pontos:\n",
      "\n",
      "    if temp < 0: print 'Congelando...'\n",
      "\n",
      "A partir da vers\u00e3o 2.5, o Python suporta a express\u00e3o:\n",
      "\n",
      "    <vari\u00e1vel> = <valor 1> if <condi\u00e7\u00e3o> else <valor 2>\n",
      "\n",
      "Na qual `<vari\u00e1vel>` receber\u00e1 `<valor 1>` se `<condi\u00e7\u00e3o>` for verdadeira e `<valor 2>`  caso contr\u00e1rio."
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