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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_weekly_chart_dates(self):
 """Returns a list of From and To tuples for the available charts."""


        doc = self._request(self.ws_prefix + ".getWeeklyChartList", True)

        seq = []
        for node in doc.getElementsByTagName("chart"):
            seq.append((node.getAttribute("from"), node.getAttribute("to")))

        return seq