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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 get_user_best(self, username, *, mode=OsuMode.osu, limit=50):
 """Get a user's best scores. Parameters username : str or int A `str` representing the user's username, or an `int` representing the user's id. mode : :class:`osuapi.enums.OsuMode` The osu! game mode for which to look up. Defaults to osu!standard. limit The maximum number of results to return. Defaults to 50, maximum 100. """

        return self._make_req(endpoints.USER_BEST, dict(
            k=self.key,
            u=username,
            type=_username_type(username),
            m=mode.value,
            limit=limit
            ), JsonList(SoloScore))