Lesson 27 - Scope.ipynb

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      "value\n"
     ]
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   "source": [
    "variable = \"value\"\n",
    "def function():\n",
    "    print(variable)\n",
    "function()"
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   "execution_count": 3,
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   "outputs": [
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     "text": [
      "other value\n"
     ]
    }
   ],
   "source": [
    "variable = \"value\"\n",
    "def function(variable):\n",
    "    print(variable)\n",
    "function(\"other value\")"
   ]
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   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "output_type": "stream",
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     "text": [
      "another value\n"
     ]
    }
   ],
   "source": [
    "variable = \"value\"\n",
    "def function(variable):\n",
    "    variable = \"another value\"\n",
    "    print(variable)\n",
    "function(\"other value\")"
   ]
  },
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   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "output_type": "error",
     "ename": "UnboundLocalError",
     "evalue": "local variable 'variable' referenced before assignment",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mUnboundLocalError\u001b[0m                         Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-5-cfc50973c985>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      3\u001b[0m     \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mvariable\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      4\u001b[0m     \u001b[0mvariable\u001b[0m \u001b[1;33m=\u001b[0m \u001b[1;34m\"another value\"\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 5\u001b[1;33m \u001b[0mfunction\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;32m<ipython-input-5-cfc50973c985>\u001b[0m in \u001b[0;36mfunction\u001b[1;34m()\u001b[0m\n\u001b[0;32m      1\u001b[0m \u001b[0mvariable\u001b[0m \u001b[1;33m=\u001b[0m \u001b[1;34m\"value\"\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      2\u001b[0m \u001b[1;32mdef\u001b[0m \u001b[0mfunction\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 3\u001b[1;33m     \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mvariable\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m      4\u001b[0m     \u001b[0mvariable\u001b[0m \u001b[1;33m=\u001b[0m \u001b[1;34m\"another value\"\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      5\u001b[0m \u001b[0mfunction\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;31mUnboundLocalError\u001b[0m: local variable 'variable' referenced before assignment"
     ]
    }
   ],
   "source": [
    "variable = \"value\"\n",
    "def function():\n",
    "    print(variable)\n",
    "    variable = \"another value\"\n",
    "function()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "output_type": "stream",
     "name": "stdout",
     "text": [
      "value\n"
     ]
    }
   ],
   "source": [
    "variable = \"value\"\n",
    "def function():\n",
    "    global variable\n",
    "    print(variable)\n",
    "    variable = \"another value\"\n",
    "function()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "output_type": "stream",
     "name": "stdout",
     "text": [
      "value\nvalue\n"
     ]
    }
   ],
   "source": [
    "variable = \"value\"\n",
    "def function():\n",
    "    print(variable)\n",
    "function()\n",
    "print(variable)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "output_type": "stream",
     "name": "stdout",
     "text": [
      "other value\nvalue\n"
     ]
    }
   ],
   "source": [
    "variable = \"value\"\n",
    "def function(variable):\n",
    "    print(variable)\n",
    "function(\"other value\")\n",
    "print(variable)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "output_type": "stream",
     "name": "stdout",
     "text": [
      "value\nanother value\n"
     ]
    }
   ],
   "source": [
    "variable = \"value\"\n",
    "def function():\n",
    "    global variable\n",
    "    print(variable)\n",
    "    variable = \"another value\"\n",
    "function()\n",
    "print(variable)"
   ]
  },
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   "cell_type": "code",
   "execution_count": null,
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   "outputs": [],
   "source": []
  }
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