Updated Understanding and debugging Nimbus EVM JSON tests (markdown)

Understanding-and-debugging-Nimbus-EVM-JSON-tests.md

@@ -175,8 +175,25 @@ Some terminals don't support colour output and in this case you will see lots of
 ### py-evm
 
 ```
-pytest -s -k fixtures/GeneralStateTests/stRefundTest/refund_OOG.json
+pytest -s -k fixtures/GeneralStateTests/stAttackTest/ContractCreationSpam.json tests/json-fixtures/test_state.py --fork Homestead
 ```
+Installation hints:
+- use a virtualenv
+- `pip install -e .[dev]` might fail with a dependency conflict (which you can see later on with `pip check`). You work around that by manually downgrading the offending packages, like this:
+
+```
+pip install pluggy==0.7.1
+pip install idna==2.7
+# as of 2018-12-06, you also need:
+pip install -e ./trinity-external-plugins/examples/peer_count_reporter
+```
+- upstream runs tests using tox, so start from there to get to the relevant `pytest` arguments:
+```
+tox -l
+tox -e py36-native-state-homestead
+pytest tests/json-fixtures/test_state.py --fork Homestead
+```
+
 ### go-ethereum
 
 ```