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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_weekday_parameters(self, filename='shlp_weekday_factors.csv'):
 """ Retrieve the weekday parameter from csv-file Parameters filename : string name of file where sigmoid factors are stored """

        file = os.path.join(self.datapath, filename)
        f_df = pd.read_csv(file, index_col=0)

        tmp_df = f_df.query('shlp_type=="{0}"'.format(self.shlp_type)).drop(
            'shlp_type', axis=1)

        tmp_df['weekdays'] = np.array(list(range(7))) + 1

        return np.array(list(map(float, pd.DataFrame.merge(
            tmp_df, self.df, left_on='weekdays', right_on='weekday',
            how='inner', left_index=True).sort_index()['wochentagsfaktor'])))