from __future__ import not available with subprocess debugging -c

[belonesox]

Environment data

• VS Code version:
  Version: 1.56.2
  Commit: 054a9295330880ed74ceaedda236253b4f39a335
  Date: 2021-05-12T16:45:26.313Z
  Electron: 12.0.4
  Chrome: 89.0.4389.114
  Node.js: 14.16.0
  V8: 8.9.255.24-electron.0
  OS: Linux x64 5.11.22-100.fc32.x86_64

• Extension version (available under the Extensions sidebar): v2021.5.842923320

• OS and version: 5.11.22-100.fc32.x86_64 Fedora VERSION="32"

• Python version (& distribution if applicable, e.g. Anaconda): Python 3.8.10

• Type of virtual environment used (N/A | venv | virtualenv | conda | ...): N/A

• Value of the python.languageServer setting: Default

Expected behaviour

Consider following gist
https://gist.github.com/belonesox/eb61ab3b31a0a5904f6ed7fa2840fb34

When we run it with python or "Run without debugging", all OK

[stas@stas-fomin-hp8770 wtf-future]$  cd /home/stas/projects/wtf-future ; /usr/bin/env /usr/bin/python /home/stas/.vscode/extensions/ms-python.python-2021.5.842923320/pythonFiles/lib/python/debugpy/launcher 42687 -- /home/stas/projects/wtf-future/wtf-future.py 
b'2222\n111\n'
b''
0

I got same results if I import debugpy, insert «breakpoint()», debugging with pdb, etc.

I expect same result, if I run this with "Start Debugging"

Actual behaviour

If I run this with "Start Debugging" I got

[stas@stas-fomin-hp8770 wtf-future]$  /usr/bin/env /usr/bin/python /home/stas/.vscode/extensions/ms-python.python-2021.5.842923320/pythonFiles/lib/python/debugpy/launcher 34191 -- /home/stas/projects/wtf-future/wtf-future.py 
b''
b'  File "<string>", line 2\nSyntaxError: from __future__ imports must occur at the beginning of the file\n'
1

Steps to reproduce:

• got https://gist.github.com/belonesox/eb61ab3b31a0a5904f6ed7fa2840fb34
• run "Start Debugging"

[fabioz]

I'll take a look at this.