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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 use_quandl_data(self, authtoken):
 """ Use quandl data to build conversion table """

        dfs = {}
        st = self.start.strftime("%Y-%m-%d")
        at = authtoken
        for pair in self.pairs:
            symbol = "".join(pair)
            qsym = "CURRFX/{}".format(symbol)
            dfs[symbol] = qdl.get(qsym,authtoken=at, trim_start=st)['Rate']
            
        self.build_conversion_table(dfs)