     "execution_count": 4,
     "metadata": {
      "collapsed": false
     },
     "outputs": [
      {
       "name": "stdout",
       "output_type": "stream",
       "text": [
        "Success: test_unique_chars\n"
       ]
      }
     ],
     "source": [
      "# %load test_unique_chars.py\n",
      "from nose.tools import assert_equal\n",
      "\n",
      "\n",
 
</s> remove    "execution_count": 3,
 </s> add    "execution_count": null, </s> remove    "execution_count": 4,
 </s> add    "execution_count": null, </s> remove     "    chars_set = set()\n",
    "    for char in string:\n",
    "        if char in chars_set:\n",
    "            return False\n",
    "        else:\n",
    "            chars_set.add(char)\n",
    "    return True"
 </s> add     "    # TODO: Implement me\n",
    "    pass"
   "outputs": [],
     "execution_count": 4,
     "metadata": {
      "collapsed": false
     },
   "outputs": [],
   "outputs": [],
   "outputs": [],
   "outputs": [],
   "outputs": [],
   "outputs": [],
   "outputs": [],
   "outputs": [],
   "outputs": [],
     "source": [
      "# %load test_unique_chars.py\n",
      "from nose.tools import assert_equal\n",
      "\n",
      "\n",
keep keep keep keep replace replace replace replace replace replace replace replace replace keep keep keep keep keep
 Set solution to blank for unique chars challenge. 
arrays_strings/unique_chars/unique_chars_challenge.ipynb