Quote Comma Quote in traceback

[Bjwebb]

Why is "," inserted into the traceback JSON string?

{
  "errors": [
    {
      "traceback": "{\"Traceback (most recent call last):\n\",\"  File \\\"/usr/local/lib/python2.7/dist-packages/rq/worker.py\\\", line 411, in perform_job\n    rv = job.perform()\n\",\"  File \\\"/usr/local/lib/python2.7/dist-packages/rq/job.py\\\", line 343, in perform\n    self._result = self.func(*self.args, **self.kwargs)\n\",\"  File \\\"/home/datastore/iati-datastore/iati_datastore/iatilib/crawler.py\\\", line 280, in update_activities\n    parse_resource(resource)\n\",\"  File \\\"/home/datastore/iati-datastore/iati_datastore/iatilib/crawler.py\\\", line 239, in parse_resource\n    parse_activity(new_identifiers, old_xml, resource)\n\",\"  File \\\"/home/datastore/iati-datastore/iati_datastore/iatilib/crawler.py\\\", line 197, in parse_activity\n    for activity in parse.document(resource.document, resource):\n\",\"  File \\\"/home/datastore/iati-datastore/iati_datastore/iatilib/parse.py\\\", line 485, in activities\n    yield activity(elem, resource=resource)\n\",\"  File \\\"/home/datastore/iati-datastore/iati_datastore/iatilib/parse.py\\\", line 466, in activity\n    field, data['iati_identifier'], exe),\n\",\"UnicodeEncodeError: 'ascii' codec can't encode character u'\\\\xa0' in position 19: ordinal not in range(128)\n\"}",
      "dataset": "fco-2013_0109_1",
      "datestamp": "2014-03-21T05:27:07.674086",
      "msg": "Exception in job \"iatilib.crawler.update_activities(u'https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/287672/Foreign_Office_-_Programme_Spend_-_2013-14.xml')\"",
      "resource_url": "https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/287672/Foreign_Office_-_Programme_Spend_-_2013-14.xml",
      "logger": "job iatilib.crawler.update_activities"
    }
  ]
}