NeoMatlabIO doesn't save groups and imagesequences to .mat

[vonaviv]

Describe the bug
I created a block (recording session) with multiple segments (trials), which include multiple spike-trains and one image sequence. After saving in .mat format and later reloading it there are no image sequence entries.
Also, I created a group for each channel which were assigned to the block as parent. They are also not retrieved.
If I open .mat file in Matlab there are no groups and image sequences as well.

To Reproduce
from neo.io import NeoMatlabIO

session # "session" is a block with multiple segments with image sequences.
session .groups # has 128 groups
session.segments[0].imagesequences # a list with one ImageSequence()

w = NeoMatlabIO(filename)
w.write_block(session)

r = NeoMatlabIO(filename)
session = r.read_block()

session.segments[0].imagesequences # empty list
session .groups # empty list

Expected behaviour
The groups and image sequences are retrieved.

Environment:

• OS: Linux (pop os)
• Python 3.11.3
• Neo version 0.12.0
• NumPy version 1.24.3

Additional context

[apdavison]

Thank you for this report.

Indeed, NeoMatlabIO has not been updated to handle recent additions to Neo.

(The attribute NeoMatlabIO.supported_objects contains [Block, Segment, AnalogSignal, IrregularlySampledSignal, Epoch, Event, SpikeTrain], from which Group and ImageSequence are missing, so this is a known problem).

Any volunteers to make the necessary changes?

[zm711]

I linked a PR that can be reviewed to fix this.