Untitled1.ipynb

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  "signature": "sha256:4afb4ed51de9af1fc41d6a8cbb3068e359b6c0c921a1752af34ef19b037d0ef2"
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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# This code can be put in any Python module, it does not require IPython\n",
      "# itself to be running already.  It only creates the magics subclass but\n",
      "# doesn't instantiate it yet.\n",
      "from __future__ import print_function\n",
      "\n",
      "import json\n",
      "import os\n",
      "import io\n",
      "\n",
      "from IPython.core.magic import (Magics, magics_class, line_magic,\n",
      "                                cell_magic, line_cell_magic)\n",
      "from IPython.core import magic_arguments\n",
      "from IPython.core.display import display \n",
      "from IPython.utils.py3compat import unicode_type\n",
      "from IPython.utils.path import unquote_filename\n",
      "\n",
      "class JustMetadata(object):\n",
      "    def __init__(self, metadata):\n",
      "        self.metadata = metadata\n",
      "    \n",
      "    def _repr_json_(self):\n",
      "        return json.dumps(self.metadata)\n",
      "\n",
      "# The class MUST call this class decorator at creation time\n",
      "@magics_class\n",
      "class MyMagics(Magics):\n",
      "\n",
      "    \n",
      "    @magic_arguments.magic_arguments()\n",
      "    @magic_arguments.argument(\n",
      "        '-a', '--append', action='store_true', default=False,\n",
      "        help='Append contents of the cell to an existing file. '\n",
      "             'The file will be created if it does not exist.'\n",
      "    )\n",
      "    @magic_arguments.argument(\n",
      "        'filename', type=unicode_type,\n",
      "        help='file to write'\n",
      "    )\n",
      "    \n",
      "    \n",
      "    @cell_magic\n",
      "    def writefile2(self, line, cell):\n",
      "        \"\"\"Write the contents of the cell to a file.\n",
      "        \"\"\"\n",
      "        args = magic_arguments.parse_argstring(self.writefile2, line)\n",
      "        filename = os.path.expanduser(unquote_filename(args.filename))\n",
      "        \n",
      "        if os.path.exists(filename):\n",
      "            print(\"Overwriting %s\" % filename)\n",
      "        else:\n",
      "            print(\"Writing %s\" % filename)\n",
      "        \n",
      "        mode = 'a' if args.append else 'w'\n",
      "        with io.open(filename, mode, encoding='utf-8') as f:\n",
      "            f.write(cell)\n",
      "        \n",
      "        display(JustMetadata({'filename' : filename}))\n",
      "\n",
      "# In order to actually use these magics, you must register them with a\n",
      "# running IPython.  This code must be placed in a file that is loaded once\n",
      "# IPython is up and running:\n",
      "ip = get_ipython()\n",
      "# You can register the class itself without instantiating it.  IPython will\n",
      "# call the default constructor on it.\n",
      "ip.register_magics(MyMagics)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 10
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%%writefile2 file2.txt \n",
      "line cell cell3"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Overwriting file2.txt\n"
       ]
      },
      {
       "json": [
        "{\"filename\": \"file2.txt\"}"
       ],
       "metadata": {},
       "output_type": "display_data",
       "text": [
        "<__main__.JustMetadata at 0x110be7b10>"
       ]
      }
     ],
     "prompt_number": 11
    }
   ],
   "metadata": {}
  }
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