docs: def post_attachment(self, bugid, attachment):
          '''http://bugzilla.readthedocs.org/en/latest/api/core/v1/attachment.html#create-attachment'''
          assert type(attachment) is DotDict
          assert 'data' in attachment
          assert 'file_name' in attachment
          assert 'summary' in attachment
          if (not 'content_type' in attachment): attachment.content_type = 'text/plain'
          attachment.ids = bugid
          attachment.data = base64.standard_b64encode(bytearray(attachment.data, 'ascii')).decode('ascii')
  
          return self._post('bug/{bugid}/attachment'.format(bugid=bugid), json.dumps(attachment))