Networkx in version [2.4](https://networkx.github.io/documentation/stable/release/release_2.4.html) deprecated the `node` attribute of `DiGraph` and suggests using `nodes` instead. This breaks OnionPerf but luckily, it's an easy fix. Here's the error I'm getting on master: ``` Traceback (most recent call last): File "/home/phw/rcs/onionperf/venv/bin/onionperf", line 4, in <module> __import__('pkg_resources').run_script('OnionPerf==0.2rc0', 'onionperf') File "/home/phw/rcs/onionperf/venv/lib/python3.7/site-packages/pkg_resources/__init__.py", line 666, in run_script self.require(requires)[0].run_script(script_name, ns) File "/home/phw/rcs/onionperf/venv/lib/python3.7/site-packages/pkg_resources/__init__.py", line 1453, in run_script exec(script_code, namespace, namespace) File "/home/phw/rcs/onionperf/venv/lib/python3.7/site-packages/OnionPerf-0.2rc0-py3.7.egg/EGG-INFO/scripts/onionperf", line 529, in <module> File "/home/phw/rcs/onionperf/venv/lib/python3.7/site-packages/OnionPerf-0.2rc0-py3.7.egg/EGG-INFO/scripts/onionperf", line 350, in main File "/home/phw/rcs/onionperf/venv/lib/python3.7/site-packages/OnionPerf-0.2rc0-py3.7.egg/EGG-INFO/scripts/onionperf", line 401, in measure File "/home/phw/rcs/onionperf/venv/lib/python3.7/site-packages/OnionPerf-0.2rc0-py3.7.egg/onionperf/measurement.py", line 239, in run File "/home/phw/rcs/onionperf/venv/lib/python3.7/site-packages/OnionPerf-0.2rc0-py3.7.egg/onionperf/measurement.py", line 315, in __start_tgen_client File "/home/phw/rcs/onionperf/venv/lib/python3.7/site-packages/OnionPerf-0.2rc0-py3.7.egg/onionperf/measurement.py", line 341, in __start_tgen File "/home/phw/rcs/onionperf/venv/lib/python3.7/site-packages/OnionPerf-0.2rc0-py3.7.egg/onionperf/model.py", line 66, in __init__ File "/home/phw/rcs/onionperf/venv/lib/python3.7/site-packages/OnionPerf-0.2rc0-py3.7.egg/onionperf/model.py", line 74, in generate AttributeError: 'DiGraph' object has no attribute 'node' ```