code: def pop_bool(self, key: str, default: Any = DEFAULT) -> bool:
          
          value = self.pop(key, default)
          if value is None:
              return None
          elif isinstance(value, bool):
              return value
          elif value == "true":
              return True
          elif value == "false":
              return False
          else:
              raise ValueError("Cannot convert variable to bool: " + value)
docs: Performs a pop and coerces to a bool.