docs: def register(self, name, option):
          """Register a new option with the namespace.
  
          Args:
              name (str): The name to register the option under.
              option (option.Option): The option object to register.
  
          Raises:
              TypeError: If the option is not an option.Option object.
              ValueError: If the name is already registered.
          """
          if name in self._options:
  
              raise ValueError("Option {0} already exists.".format(name))
  
          if not isinstance(option, opt.Option):
  
              raise TypeError("Options must be of type Option.")
  
          self._options[name] = option