Python interpreter not detected via C-c C-p and doesn't print anything

[parvizfarnia]

Hello everyone and Merry Christmas

My environment:

- Emacs version 29.1
- Python version : 3.12.0 (64 bit)
- OS : Windows 11

Here is how I proceeded to install python-lsp-server:

• First, I created a new virtual environment (Python-3.12.0-64 bit)
• Second, I enabled this new environment and within the same terminal I run emacs in background (start /B runemacs.exe)
• And then, I returned to the same terminal and I installed the following packages:

pip install "python-lsp-server[all]"
pip install pylsp-mypy
pip install python-lsp-isort
pip install pylsp-rope
pip install pyls-memestra
pip install pylsp-rope
pip install python-lsp-ruff

Then I came back to Emacs and I installed the following packages from MELPA:

M-x package-install [RET] lsp-mode [RET]
M-x package-install [RET] lsp-ui [RET]
M-x package-install [RET] flycheck [RET]
M-x package-install [RET] helm-lsp [RET]
M-x package-install [RET] lsp-treemacs [RET]

And finally I put the following in my Emacs configuration file (org file) to enable lsp-mode for Python:

  (use-package lsp-ui)
  (lsp-treemacs-sync-mode 1)
  (define-key lsp-mode-map [remap xref-find-apropos] #'helm-lsp-workspace-symbol)
  (require 'lsp-mode)
  (add-hook 'python-mode-hook #'lsp)

Generally, it seems that it is working. However, I have currently two issues:

• As I said, first, I enabled my Python virtual environment and then, within the very same terminal, I launched Emacs in background. My requirement is that lsp should consider as Python interpreter, the same interpreter of the currently running virtual environment (Python 3.12.0). However, due to some technical constraints, I have not added that interpreter in my PATH environment variable. Currently only Python 3.10 is in my PATH. Consequently when I run C-c C-p to start a Python process, it opens a Python 3.10 shell instead of 3.12. Therefore, I need a way to tell lsp client to take the very Python interpreter used by lsp-server, which is that of the current running virtual environment.

• After running C-c C-p if I come back to my Python program buffer and do C-c C-c in order to send the current buffer to Python process for running, nothing happens and the result is not printed, there is no output. Consider the following example:

def main():
    """Print Hello."""
    print("Hello World")


if __name__ == "__main__":
    main()

If I do C-c C-c within the buffer containing the above program, then the only thing that happens in *Python* buffer (Python process launched via C-c C-p) is a new prompt line >>> which is added and that's all. No "Hello World" message is printed as if the Standard Output was not available. I even introduced a syntax error in the program to see whether doing C-c C-c will cause the *Python* process buffer print an error message, but again, the same problem only a new prompt line >>> is added. I wonder whether this *Python* process communicates at all with the buffer containing my Python program.

Therefore, I would like to know what is wrong with my configuration and how to solve these issues.

Thanks in advance.

[parvizfarnia]

I managed to solve the first problem. I added the following to my Emacs init.el file :

(custom-set-variables
;; =============== Other variables ================
	'(python-shell-interpreter "python"))

But the other problem persists, that is, doing C-c C-c doesn't print anything inside *Python* buffer.

[parvizfarnia]

Any idea about why C-c C-c doesn't print the program output ?