What does this code fragment do?

[rdx]

Given: brain_live_features is an array of ints ...

    live_features = brain_live_features + 2
    live_features = list(live_features)
    live_features = [0, 1] + live_features
    live_features = np.array(live_features).astype('int32')

My question is, what does this code do? When I type the first line into interactive python it gives me an error,

Error:
can only concatenate list (not "int") to list

My best guess is that we are adding the value 2 to each element of brain_live_features to adjust these indices before we prepend two new elements [0, 1].

[stranac]

Seems to me that by "an array of ints" they are referring to a numpy array...

[rdx]

Yes, I think you're right. If I say
blf = np.array( ...
then it seems to work. That seems to use the next line,
lf = list( lf )
to convert the np.array into a list so it can be concat'd.

Thank you.