code: def set_options_from_JSON(self, filename):
          
          if not os.path.isfile(filename):
              raise IOError("File {0} not found".format(filename))
          data_str = "".join([x.strip() for x in open(filename).readlines()])
          data_dict = json.loads(data_str)
          self.set_options_from_dict(data_dict, filename)
docs: Load options from a YAML-formated file.
  
          :param str filename: File from which to load the options.
  
          :raise:
              :IOError: If ``filename`` does not exist.