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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 concat(self, *dss, **kwargs):
 """ Concatenate dataswim instances from and set it to the main dataframe :param dss: dataswim instances to concatenate :type dss: Ds :param kwargs: keyword arguments for ``pd.concat`` """

        try:
            df = pd.DataFrame()
            for dsx in dss:
                df = pd.concat([df, dsx.df], **kwargs)
            self.df = df
        except Exception as e:
            self.err(e, "Can not concatenate data")