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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 _make_df(rows):
 """Internal Method to make and clean the dataframe in preparation for sending to Parquet"""


    # Make DataFrame
    df = pd.DataFrame(rows).set_index('ts')

    # TimeDelta Support: https://issues.apache.org/jira/browse/ARROW-835
    for column in df.columns:
        if(df[column].dtype == 'timedelta64[ns]'):
            print('Converting timedelta column {:s}...'.format(column))
            df[column] = df[column].astype(str)
    return df