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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 update(self, command=None, **kwargs):
 """update data, which is usually passed in ArgumentParser initialization e.g. command.update(prog="foo") """

        if command is None:
            argparser = self.argparser
        else:
            argparser = self[command]

        for k,v in kwargs.items():
            setattr(argparser, k, v)