[Tutor] Am I storeing up problems ?

[Alan Gauld]

> I needed to copy this matrix to 'self.old_data', so I have been
using
> .deepcopy(), which works OK but is SLOW .... (12+ secs)

Are you sure you need to copy it./ A simple reassignment should work
and then reconstruct the structure using fresh lists/dictionary etc.
That should work faster.

Alan G.