code: def get_json(self, key, default=None):
          
          value = self.get_str(key)
          if value is not None:
              value = from_json(value)
              if value is not None:
                  return value
  
          if isinstance(default, (dict, list)):
              return default
  
          return from_json(default)
docs: Args:
              key (str | unicode): Key to lookup
              default (str | unicode | dict | list | None): Default to use if key is not configured
  
          Returns:
              (dict | list | str | int | None): Deserialized json, if any