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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_top_artists(self, limit=None, cacheable=True):
 """Returns a sequence of the most played artists."""

        params = self._get_params()
        if limit:
            params["limit"] = limit

        doc = self._request("geo.getTopArtists", cacheable, params)

        return _extract_top_artists(doc, self)