The call to get chain constituents can be simplified compared to the example @chavalit-jintamalit provided.
tmp_df, err = ek.get_data('0#LCO:',['DSPLY_NAME'])
futures = tmp_df['Instrument'].tolist()[1:]
ek.get_timeseries(futures, start_date='2019-07-01', end_date='2019-08-01')
0#LCO: is a chain RIC.
You can get all the underlying RIC by following this code:
Then you can get time series on each individual underlying RIC code: