which python version can run best ?

[handsome12345]

after i installed numpy pandas and so on .
i run 01_什么是量化金融 the first part script:

========== 导入本实验需要的库 ==========

import numpy as np # 做数值计算（随机数、累乘价格等）
import pandas as pd # 处理表格数据（像 Excel 一张表）
import matplotlib.pyplot as plt # 画折线图、对比图

========== 让图表能正确显示中文 ==========

plt.rcParams['font.sans-serif'] = ['SimHei'] # 指定中文字体（Windows 常用黑体）
plt.rcParams['axes.unicode_minus'] = False # 让坐标轴上的负号正常显示
np.random.seed(7) # 固定随机种子：每次运行随机数相同，方便对照
......

with this error :
D:\develop\pycharmCode\venv\Scripts\python.exe D:\develop\pycharmCode\Invest\quant-for-beginners_01.py
Traceback (most recent call last):
File "D:\develop\pycharmCode\Invest\quant-for-beginners_01.py", line 42, in
fig, axes = plt.subplots(2, 1, figsize=(11, 8), sharex=True) # 2行1列子图，共用横轴
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib\pyplot.py", line 1432, in subplots
fig = figure(**fig_kw)
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib_api\deprecation.py", line 454, in wrapper
return func(*args, **kwargs)
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib\pyplot.py", line 773, in figure
manager = new_figure_manager(
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib\pyplot.py", line 348, in new_figure_manager
_warn_if_gui_out_of_main_thread()
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib\pyplot.py", line 338, in _warn_if_gui_out_of_main_thread
if (_get_required_interactive_framework(_get_backend_mod()) and
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib\pyplot.py", line 207, in get_backend_mod
switch_backend(dict.getitem(rcParams, "backend"))
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib\pyplot.py", line 252, in switch_backend
switch_backend(candidate)
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib\pyplot.py", line 265, in switch_backend
backend_mod = importlib.import_module(
File "C:\Users\huajie.yuan\AppData\Local\Programs\Python\Python39\lib\importlib_init.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "", line 1030, in _gcd_import
File "", line 1007, in _find_and_load
File "", line 986, in _find_and_load_unlocked
File "", line 680, in _load_unlocked
File "", line 850, in exec_module
File "", line 228, in _call_with_frames_removed
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib\backends\backend_qtagg.py", line 12, in
from .backend_qt import QtCore, QtGui, _BackendQT, FigureCanvasQT
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib\backends\backend_qt.py", line 72, in
_MODIFIER_KEYS = [
File "D:\develop\pycharmCode\venv\lib\site-packages\matplotlib\backends\backend_qt.py", line 73, in
(_to_int(getattr(_enum("QtCore.Qt.KeyboardModifier"), mod)),
TypeError: int() argument must be a string, a bytes-like object or a number, not 'KeyboardModifier'

[yibohere]

Hi @handsome12345, thanks for reporting this!

Short answer on Python version: We recommend Python 3.10 or 3.11 (see README). Python 3.9 can work, but 3.10+ is what we test against.

About your error: This is usually not a Python-version problem. The traceback points to matplotlib + Qt backend (KeyboardModifier in backend_qt.py). That often happens when:

• matplotlib is outdated vs PyQt6/PySide6, or
• running notebook code as a plain .py script in PyCharm with a GUI backend.

Try these (in order):

1. Use Jupyter (recommended for this repo)
   pip install -r requirements.txt
   jupyter lab

2. Fresh venv with Python 3.10+
   python -m venv venv
   venv\Scripts\activate
   pip install -U pip
   pip install -r requirements.txt

3.If you must run as .py, set backend before import matplotlib.pyplot:

import matplotlib
matplotlib.use("TkAgg") # or "Agg" if you only save figures, no popup window
import matplotlib.pyplot as plt

4.Upgrade matplotlib
pip install -U matplotlib

If it still fails, please paste:
python --version
pip show matplotlib PyQt6 PySide6 PyQt5
whether you run Notebook or .py script

Happy to help debug further!