Networkx < 2.4

[mrvollger]

Hi Jason,

With the release of networkx 2.4 the syntax G.node is removed in favor of G.nodes (https://networkx.github.io/documentation/stable/release/release_2.4.html), and running Peregrine with this version of networkx results in the following error in the assembly stage: AttributeError: 'DiGraph' object has no attribute 'node'

I was able to fix this by specifically installing networkx==2.2.

I would consider specifying an exact networkx version in setup_pypy.py. Perhaps: install_requires=["networkx==2.2"], instead of: install_requires=["networkx>=2.2"],

I know you recommend using docker to avoid these exact kind of issues, so feel free to close. But I wanted to post for others who might be trying conda installs.

Thanks! Mitchell