How to get rid of python error when starting webpacker server?

Question

Ruby on Rails

There was a working draft. I changed the operating system from ubuntu 19 to 20.
I start the project: Out of
foreman start -f Procfile.dev
nowhere, an error appeared:

00h00m00s 0/0: : ERROR: [Errno 21] Is a directory: 'bin'
CRITICAL:root:Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/cliapp/app.py", line 182, in _run
    self.settings.load_configs()
  File "/usr/lib/python3/dist-packages/cliapp/settings.py", line 829, in load_configs
    self._read_ini(pathname, f)
  File "/usr/lib/python3/dist-packages/cliapp/settings.py", line 838, in _read_ini
    cp.readfp(f)
  File "/usr/lib/python3.8/configparser.py", line 763, in readfp
    self.read_file(fp, source=filename)
  File "/usr/lib/python3.8/configparser.py", line 718, in read_file
    self._read(f, source)
  File "/usr/lib/python3.8/configparser.py", line 1082, in _read
    raise MissingSectionHeaderError(fpname, lineno, line)
configparser.MissingSectionHeaderError: File contains no section headers.
file: '/home/ya/project/config/webpack/development.js', line: 1
"process.env.NODE_ENV = process.env.NODE_ENV || 'development'\n"

I don’t understand where the python came from, okay, webpacker is magic)). This error when starting the frontend, i.e. webpacker-dev-server does not start:

ruby bin/webpack-dev-server  --content-base src --hot --inline --watch

Search by mistake

configparser.MissingSectionHeaderError: File contains no section headers.

gives me unintelligible answers. Help with an idea where to dig.

Answer 1

The cmdtest package may have been installed by mistake, which contains the non-kosher yarn program.
Try uninstalling it:
sudo apt remove cmdtest
And then reinstalling yarn Problem
Root: https://github.com/yarnpkg/yarn/issues/7892
https://github.com/forem/forem/issues/11745#issuec...