StringIO.ipynb

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   "source": [
    "# StringIO \n",
    "\n",
    "The StringIO module implements an in-memory file like object. This object can then be used as input or output to most functions that would expect a standard file object.\n",
    "\n",
    "The best way to show this is by example:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": true
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   "outputs": [],
   "source": [
    "import StringIO"
   ]
  },
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   "cell_type": "code",
   "execution_count": 16,
   "metadata": {
    "collapsed": true
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   "source": [
    "# Arbitrary String\n",
    "message = 'This is just a normal string.'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "metadata": {
    "collapsed": true
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   "outputs": [],
   "source": [
    "# Use StringIO method to set as file object\n",
    "f = StringIO.StringIO(message)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Now we have an object *f* that we will be able to treat just like a file. For example:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 30,
   "metadata": {
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   "outputs": [
    {
     "data": {
      "text/plain": [
       "''"
      ]
     },
     "execution_count": 30,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "f.read()"
   ]
  },
  {
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   "source": [
    "We can also write to it:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {
    "collapsed": false
   },
   "outputs": [],
   "source": [
    "f.write(' Second line written to file like object')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "# Reset cursor just like you would a file\n",
    "f.seek(0)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 29,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'This is just a normal string. Second line written to file like object'"
      ]
     },
     "execution_count": 29,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Read again\n",
    "f.read()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Great! Now you've seen how we can use StringIO to turn normal strings into in-memory file objects in our code. This kind of action has various use cases, especially in web scraping cases where you want to read some string you scraped as a file.\n",
    "\n",
    "For more info on StringIO check out the documentation:https://docs.python.org/2/library/stringio.html"
   ]
  }
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