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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def strategy(self, *names, **kwargs):
 """ StrategyDict wrapping method for adding a new strategy. Parameters *names : Positional arguments with all names (strings) that could be used to call the strategy to be added, to be used both as key items and as attribute names. keep_name : Boolean keyword-only parameter for choosing whether the ``__name__`` attribute of the decorated/wrapped function should be changed or kept. Defaults to False (i.e., changes the name by default). Returns ------- A decorator/wrapper function to be used once on the new strategy to be added. Example ------- Let's create a StrategyDict that knows its name: Add a first strategy ``swapcase``, using this method as a decorator factory: Let's do it again, but wrapping the strategy functions inline. First two strategies have multiple names, the last keeps the function name, which would otherwise be replaced by the first given name: We can now iterate through the strategies to call them or see their function names ['JUST A TEST', 'Just a Test', 'jUST A tEST', 'just a test'] ['<lambda>', 'lower', 'swapcase', 'upper'] Calling a single strategy: 'testing' 'TESTING' 'tEsTiNg' 'tEsTiNg' 'TESTING' Hint ---- Default strategy is the one stored as the ``default`` attribute, you can change or remove it at any time. When removing all keys that are assigned to the default strategy, the default attribute will be removed from the StrategyDict instance as well. The first strategy added afterwards is the one that will become the new default, unless the attribute is created or changed manually. """

    def decorator(func):
      keep_name = kwargs.pop("keep_name", False)
      if kwargs:
        key = next(iter(kwargs))
        raise TypeError("Unknown keyword argument '{}'".format(key))
      if not keep_name:
        func.__name__ = str(names[0])
      self[names] = func
      return self
    return decorator