Cannot start JM on regtest network

Hello, I'd like to play a bit with JM on regtest.

I'm following this guide here, https://github.com/JoinMarket-Org/joinmarket-clientserver/blob/master/docs/TESTING.md

The problem is that when I reach the point to run pytest it crashes with KeyError: 'BREAK_LOOP'

(jmvenv)$ pytest --btcconf=/path/to/bitcoin.conf --btcroot=/path/to/bitcoin/bin/ --btcpwd=123456abcdef --nirc=2 --ignore test/test_full_coinjoin.py -p no:warnings (obvuiosly paths are customized)

Here follow the stacktrace: Traceback (most recent call last): File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/bin/pytest", line 8, in <module> sys.exit(main()) File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/_pytest/config/__init__.py", line 73, in main config = _prepareconfig(args, plugins) File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/_pytest/config/__init__.py", line 223, in _prepareconfig return pluginmanager.hook.pytest_cmdline_parse( File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/pluggy/hooks.py", line 286, in __call__ return self._hookexec(self, self.get_hookimpls(), kwargs) File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/pluggy/manager.py", line 93, in _hookexec return self._inner_hookexec(hook, methods, kwargs) File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/pluggy/manager.py", line 84, in <lambda> self._inner_hookexec = lambda hook, methods, kwargs: hook.multicall( File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/pluggy/callers.py", line 203, in _multicall gen.send(outcome) File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/_pytest/helpconfig.py", line 89, in pytest_cmdline_parse config = outcome.get_result() File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/pluggy/callers.py", line 80, in get_result raise ex[1].with_traceback(ex[2]) File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/pluggy/callers.py", line 187, in _multicall res = hook_impl.function(*args) File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/_pytest/config/__init__.py", line 794, in pytest_cmdline_parse self.parse(args) File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/_pytest/config/__init__.py", line 1000, in parse self._preparse(args, addopts=addopts) File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/_pytest/config/__init__.py", line 948, in _preparse self.pluginmanager.load_setuptools_entrypoints("pytest11") File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/pluggy/manager.py", line 299, in load_setuptools_entrypoints plugin = ep.load() File "/usr/local/opt/python@3.8/Frameworks/Python.framework/Versions/3.8/lib/python3.8/importlib/metadata.py", line 77, in load module = import_module(match.group('module')) File "/usr/local/opt/python@3.8/Frameworks/Python.framework/Versions/3.8/lib/python3.8/importlib/__init__.py", line 127, in import_module return _bootstrap._gcd_import(name[level:], package, level) File "<frozen importlib._bootstrap>", line 1014, in _gcd_import File "<frozen importlib._bootstrap>", line 991, in _find_and_load File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked File "<frozen importlib._bootstrap>", line 671, in _load_unlocked File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/_pytest/assertion/rewrite.py", line 143, in exec_module exec(co, module.__dict__) File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/pytest_cov/plugin.py", line 6, in <module> from coverage.misc import CoverageException File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/coverage/__init__.py", line 13, in <module> from coverage.control import Coverage, process_startup File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/coverage/control.py", line 30, in <module> from coverage.python import PythonFileReporter File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/coverage/python.py", line 11, in <module> from coverage.parser import PythonParser File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/coverage/parser.py", line 320, in <module> OP_BREAK_LOOP = _opcode('BREAK_LOOP') File "/Users/nolith/src/crypto/joinmarket-clientserver/jmvenv/lib/python3.8/site-packages/coverage/parser.py", line 278, in _opcode return dis.opmap[name] KeyError: 'BREAK_LOOP'

Any suggestions?