code: def clean_server_response(self, resp_dict):
          
  
          # change all the keys from unicode to string
          d = {}
          for key, value in resp_dict.items():
              d[str(key)] = value
          resp_dict = d
          for key, value in resp_dict.items():
              if type(value) is str or isinstance(value, six.string_types):
                  if re.match('-', value):
                      try:
                          if float(value) or int(value):
                              dataType = True
                      except ValueError:
                          resp_dict[key] = None
                  elif re.search(r'^[0-9,.]+$', value):
                      # replace , to '', and type cast to int
                      resp_dict[key] = float(re.sub(',', '', value))
                  else:
                      resp_dict[key] = str(value)
          return resp_dict
docs: cleans the server reponse by replacing:
              '-'     -> None
              '1,000' -> 1000
          :param resp_dict:
          :return: dict with all above substitution