Hey there, let's work through this PyCharm remote debugging error you're hitting. First, let's recap the key details from your setup:

Your project only has my_pro.py with this minimal code:

if __name__ == '__main__':
    print('DD')
    print()

And you're getting this traceback:

Traceback (most recent call last):
  File "/home/www/.pycharm_helpers/pydev/_pydevd_bundle/pydevd_trace_dispatch.py", line 55, in <module>
    from _pydevd_bundle.pydevd_cython_wrapper import trace_dispatch as _trace_dispatch, global_cache_skips, global_cache_frame_skips, fix_top_level_trace_and_get_trace_func
  File "/home/www/.pycharm_helpers/pydev/_pydevd_bundle/pydevd_cython_wrapper.py", line 48, in <module>
    raise exc
ImportError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/www/.pycharm_helpers/pydev/pydevd.py", line 49, in <module>
    from _pydevd_bundle.pydevd_trace_dispatch import (
  File "/home/www/.pycharm_helpers/pydev/_pydevd_bundle/pydevd_trace_dispatch.py", line 63, in <module>
    delete_old_compiled_extensions()
  File "/home/www/.pycharm_helpers/pydev/_pydevd_bundle/pydevd_trace_dispatch.py", line 18, in delete_old_compiled_extensions
    import _pydevd_bundle_ext
ModuleNotFoundError: No module named '_pydevd_bundle_ext'
Process finished with exit code 1

This error happens because PyCharm's remote debugging helper scripts (stored in /home/www/.pycharm_helpers on your server) are either corrupted, outdated, or incompatible with your Python/PyCharm version. Here are three fixes that should resolve this:

1. Re-upload fresh helper scripts to your server #

The most common fix is to wipe the existing helper folder and let PyCharm re-send the latest compatible files:

• Connect to your remote server via SSH and run this command to delete the old helpers:

  rm -rf /home/www/.pycharm_helpers
  

• Go back to PyCharm and restart your remote debugging session. PyCharm will automatically detect the missing folder and upload fresh copies of the helper scripts, including the required _pydevd_bundle_ext module.

If you prefer to trigger the upload manually through PyCharm settings:

• Navigate to File → Settings → Project: [Your Project Name] → Python Interpreter
• Select your remote interpreter, click the gear icon → Show All
• Choose your remote interpreter, click the ... button → Configure Remote Python Interpreter
• Switch to the Deployment tab and click Upload helper scripts to the server

2. Check Python-PyCharm version compatibility #

Mismatched versions between your remote Python and PyCharm can break the compiled _pydevd_bundle_ext module:

• Run python --version or python3 --version on your remote server to confirm your Python version.
• Make sure your PyCharm version supports that Python release. For example:
  • Python 3.12 requires PyCharm 2023.3+
  • Python 3.11 requires PyCharm 2022.3+
    If you're on an older PyCharm, consider updating it to match your remote Python version.

3. Disable Cython-based debugging (temporary workaround) #

If the above steps don't work, you can bypass the Cython extension entirely by disabling it in your debug config:

• Open Run → Edit Configurations
• Select your remote debug configuration
• Go to the Configuration tab, scroll down to the Debugger section
• Add -Dpydevd_use_cython=NO to the VM options field (some PyCharm versions have a checkbox labeled "Disable Cython extensions" you can tick instead)
• Save the config and restart debugging

Just to confirm: your test code is totally fine—this is 100% an issue with PyCharm's remote debugging infrastructure, not your script.

内容的提问来源于stack exchange，提问作者zhang kk