Either that site is quite old, or the author is not a GURU.
I would like to suggest HDF5 as a better solution: http://www.h5py.org/ and docs: http://docs.h5py.org/en/stable/
I would like to suggest HDF5 as a better solution: http://www.h5py.org/ and docs: http://docs.h5py.org/en/stable/