Joining and Merging MIDI Files

[shreyanmitra]

Hello,

I am brand new to Mido, and I had some few (possible elementary) questions about getting started.

1. I have two midi files. Let's call them a.mid and b.mid. How do I merge them into one midi file such that they are played simultaneously?
2. How do I concatenate them into one midi file such that they are played one after another in quick succession?

Perhaps there are functions in the API like join() or merge() that do this, but I cannot seem to find them.
Any help would be greatly appreciated @rdoursenaud @bast

[shreyanmitra]

For 1, I just appended all the tracks together into a new MidiFile using +=
For 2, I am thinking of offsetting a track by the length of the previous track. Is there an offset argument I could use in the MidiTrack.append() function?