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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_group_dataframes(self):
 """ Get group dataframes Returns ------- out : tuple or generator Group dataframes """

        if isinstance(self.data, GroupedDataFrame):
            grouper = self.data.groupby()
            # groupby on categorical columns uses the categories
            # even if they are not present in the data. This
            # leads to empty groups. We exclude them.
            return (gdf for _, gdf in grouper if not gdf.empty)
        else:
            return (self.data, )