Obtaining a sub-E-Graph

[ViciousDoormat]

Hello,
I was wondering whether there is a way to obtain a sub-E-graph given an E-Graph and a collection of root E-Class IDs

Say we have an E-Graph g representing 2*(2*a) and 4*a

[1] -> 2
[2] -> 4
[3] -> a
[4] -> [1] * [3]
[6] -> [1] * [4], [2] * [3]

Then get_subegraph(g, [4]) gives

[1] -> 2
[3] -> a
[4] -> [1] * [3]

And get_subegraph(g, [2,4]) gives

[1] -> 2
[2] -> 4
[3] -> a
[4] -> [1] * [3]