fixed nodelist and edgelist reference problem

[jimixxperez]

a = pd.DataFrame([{'a': 1, 'c': 0}, {'a': 2, 'c': 2}, {'a': 3, 'c': 5}])
b = a
b = b.loc[[0, 2]]

b =>
a c
0 1 0
2 3 5

a =>
a c
0 1 0
1 2 2
2 3 5

[T-Flet]

I am not sure whether GitHub would have notified you of this, but I opened and accepted an instance of this pull request in my fork (which was originally made precisely to have a version with fixes from issues and PRs).

The fork has now been detached and released as its own library, altair-nx, because the original has been inactive since 2020 and because the fork diverged from it considerably after a full code-base rework and the implementation of new features (e.g. curved edges, self loops, and much greater customisability).