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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 legend(self, *args, **kwargs):
 """Add a legend. Parameters *args matplotlib legend args. *kwargs matplotlib legend kwargs. Returns ------- legend """

        if "fancybox" not in kwargs.keys():
            kwargs["fancybox"] = False
        if "framealpha" not in kwargs.keys():
            kwargs["framealpha"] = 1.
        return super().legend(*args, **kwargs)