pypy3.8/3.9 pandas: TypeError: instance layout conflicts in multiple inheritance
A recent regression (worked ~3 weeks ago), when importing pandas on pypy3.8/3.9:
from pandas import Series
../pypy38-venv/lib/pypy3.8/site-packages/pandas/__init__.py:22: in <module>
from pandas.compat import is_numpy_dev as _is_numpy_dev
../pypy38-venv/lib/pypy3.8/site-packages/pandas/compat/__init__.py:15: in <module>
from pandas.compat.numpy import (
../pypy38-venv/lib/pypy3.8/site-packages/pandas/compat/numpy/__init__.py:4: in <module>
from pandas.util.version import Version
../pypy38-venv/lib/pypy3.8/site-packages/pandas/util/__init__.py:1: in <module>
from pandas.util._decorators import ( # noqa:F401
../pypy38-venv/lib/pypy3.8/site-packages/pandas/util/_decorators.py:14: in <module>
from pandas._libs.properties import cache_readonly # noqa:F401
../pypy38-venv/lib/pypy3.8/site-packages/pandas/_libs/__init__.py:13: in <module>
from pandas._libs.interval import Interval
pandas/_libs/interval.pyx:1: in init pandas._libs.interval
???
pandas/_libs/hashtable.pyx:1: in init pandas._libs.hashtable
???
pandas/_libs/missing.pyx:1: in init pandas._libs.missing
???
../pypy38-venv/lib/pypy3.8/site-packages/pandas/_libs/tslibs/__init__.py:30: in <module>
from pandas._libs.tslibs.conversion import (
pandas/_libs/tslibs/conversion.pyx:63: in init pandas._libs.tslibs.conversion
???
pandas/_libs/tslibs/parsing.pyx:1: in init pandas._libs.tslibs.parsing
???
pandas/_libs/tslibs/offsets.pyx:1: in init pandas._libs.tslibs.offsets
???
pandas/_libs/tslibs/timedeltas.pyx:61: in init pandas._libs.tslibs.timedeltas
???
pandas/_libs/tslibs/fields.pyx:22: in init pandas._libs.tslibs.fields
???
../pypy38-venv/lib/pypy3.8/site-packages/pandas/_config/__init__.py:18: in <module>
from pandas._config import config
../pypy38-venv/lib/pypy3.8/site-packages/pandas/_config/config.py:98: in <module>
class OptionError(AttributeError, KeyError):
E TypeError: instance layout conflicts in multiple inheritance
The same error on pypy3.8 and pypy3.9. Doesn't happen on pypy3.7