nb-cli installed via pipx fails when system has Python < 3.1

[afterow]

nb-cli installed via pipx fails when system has Python < 3.1

Describe the bug

When nb-cli is installed via pipx with Python 3.13, running nb command fails with PythonInterpreterError: Python 3.8 is not supported if the system's default python command points to Python 3.8.

To Reproduce

Steps to reproduce the behavior:

1. Have Python 3.8 installed and set as the default python command in system PATH
2. Install nb-cli via pipx with a newer Python version:

   pipx install nb-cli --python python3.13

3. Run nb command:

   nb

4. See error:

   nb_cli.exceptions.PythonInterpreterError: Python 3.8 is not supported.
   

Expected behavior

nb-cli should prioritize using its own Python interpreter (the one it's running in, i.e., sys.executable) when the version meets the requirement (>= 3.10), rather than always searching for python in the system PATH.

Current behavior

From meta.py#L65-L89:

@cache(ttl=None)
async def _get_env_python() -> str:
    python_to_try = WINDOWS_DEFAULT_PYTHON if WINDOWS else DEFAULT_PYTHON
    # WINDOWS_DEFAULT_PYTHON = ("python",)
    
    for python in python_to_try:
        proc = await create_process_shell(f"{python} -W ignore -c ...")

Although the NoneBot project has now removed support for Python 3.9
but On Windows, it only tries the python command from system PATH, which may point to an unsupported Python version (< 3.10), even though nb-cli itself is running in a Python 3.13 virtual environment.

Environment

• OS: Windows
• Python version (nb-cli venv): 3.13.5
• Python version (system default): 3.8.x
• nb-cli version: 1.7.4
• Installation method: pipx

Suggested fix

none

[yanyongyu]

优先查找系统内可用的 python 才是正常行为吧，pipx 使用的 python 并不一定是项目适合使用的

[afterow]

优先查找系统内可用的 python

按nb-cli部分的代码按设计来说不应该用pipx里面的环境来运行的吗？

[yanyongyu]

按nb-cli部分的代码按设计来说不应该用pipx里面的环境来运行的吗？

pipx 所使用的环境应该是安装工具所用环境，并不一定是项目需要的环境