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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 save_dataframes(self, outdir, prefix='df_'):
 """Save all attributes that start with "df" into a specified directory. Args: outdir (str):
 Path to output directory prefix (str):
 Prefix that dataframe attributes start with """

        # Get list of attributes that start with "df_"
        dfs = list(filter(lambda x: x.startswith(prefix), dir(self)))

        counter = 0
        for df in dfs:
            outpath = ssbio.utils.outfile_maker(inname=df, outext='.csv', outdir=outdir)
            my_df = getattr(self, df)
            if not isinstance(my_df, pd.DataFrame):
                raise TypeError('{}: object is not a Pandas DataFrame'.format(df))

            if my_df.empty:
                log.debug('{}: empty dataframe, not saving'.format(df))
            else:
                my_df.to_csv(outpath)
                log.debug('{}: saved dataframe'.format(outpath))
                counter += 1

        log.debug('Saved {} dataframes at {}'.format(counter, outdir))