安装（ubuntu）python3.9后，安装一些pip包失败：
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/usr/lib/python3/dist-packages/setuptools/__init__.py", line 14, in <module>
from setuptools.dist import Distribution, Feature
File "/usr/lib/python3/dist-packages/setuptools/dist.py", line 24, in <module>
from setuptools.depends import Require
File "/usr/lib/python3/dist-packages/setuptools/depends.py", line 7, in <module>
from .py33compat import Bytecode
File "/usr/lib/python3/dist-packages/setuptools/py33compat.py", line 54, in <module>
unescape = getattr(html, 'unescape', html_parser.HTMLParser().unescape)
AttributeError: 'HTMLParser' object has no attribute 'unescape'
----------------------------------------
ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.