ImportError on macOS BigSur

[DavidHazel]

on macOS BigSUR

pip install chardet

Results in import error

(venv) ➜  ivydata pip install chardet         
Traceback (most recent call last):
  File "/Path/to/project/venv/bin/pip", line 8, in <module>
    sys.exit(main())
  File "/Path/to/project/venv/lib/python3.8/site-packages/pip/_internal/cli/main.py", line 72, in main
    command = create_command(cmd_name, isolated=("--isolated" in cmd_args))
  File "/Path/to/project/venv/lib/python3.8/site-packages/pip/_internal/commands/__init__.py", line 158, in create_command
    module = importlib.import_module(module_path)
  File "/usr/local/Cellar/python@3.8/3.8.5/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 "<frozen importlib._bootstrap_external>", line 783, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/Path/to/project/venv/lib/python3.8/site-packages/pip/_internal/commands/install.py", line 15, in <module>
    from pip._internal.cli.req_command import RequirementCommand, with_cleanup
  File "/Path/to/project/venv/lib/python3.8/site-packages/pip/_internal/cli/req_command.py", line 16, in <module>
    from pip._internal.index.collector import LinkCollector
  File "/Path/to/project/venv/lib/python3.8/site-packages/pip/_internal/index/collector.py", line 16, in <module>
    from pip._vendor import html5lib, requests
  File "/Path/to/project/venv/lib/python3.8/site-packages/pip/_vendor/requests/__init__.py", line 44, in <module>
    from pip._vendor import chardet
  File "/Path/to/project/venv/lib/python3.8/site-packages/pip/_vendor/chardet/__init__.py", line 19, in <module>
    from .universaldetector import UniversalDetector
  File "/Path/to/project/venv/lib/python3.8/site-packages/pip/_vendor/chardet/universaldetector.py", line 48, in <module>
    from .sbcsgroupprober import SBCSGroupProber
  File "/Path/to/project/venv/lib/python3.8/site-packages/pip/_vendor/chardet/sbcsgroupprober.py", line 45, in <module>
    from .langthaimodel import TIS_620_THAI_MODEL
ImportError: cannot import name 'TIS_620_THAI_MODEL' from 'pip._vendor.chardet.langthaimodel' (/Path/to/project/venv/lib/python3.8/site-packages/pip/_vendor/chardet/langthaimodel.py)

(venv) ➜ python --version
Python 3.8.5
(venv) ➜ pip --version
pip 21.0.1 from /venv/lib/python3.8/site-packages/pip (python 3.8)