The mbed device-management command fails with Python 3.8

[fkjagodzinski]

Description of defect

Executing a simple mbed device-management --help command in a clean Python environment fails with:

Traceback (most recent call last):
  File "/home/filip/workspace/mbed-os/tools/device_management.py", line 27, in <module>
    from manifesttool import create, parse, verify, cert, init, update
  File "/home/filip/workspace/mbed-os/venv/lib/python3.8/site-packages/manifesttool/create.py", line 19, in <module>
    from manifesttool.v1.create import main as create_v1
  File "/home/filip/workspace/mbed-os/venv/lib/python3.8/site-packages/manifesttool/v1/create.py", line 37, in <module>
    from manifesttool import utils, codec, errorhandler, defaults
  File "/home/filip/workspace/mbed-os/venv/lib/python3.8/site-packages/manifesttool/utils.py", line 32, in <module>
    from future.moves.urllib.request import urlopen, Request
  File "/home/filip/workspace/mbed-os/venv/lib/python3.8/site-packages/future/moves/urllib/request.py", line 9, in <module>
    from urllib.request import (getproxies,
ImportError: cannot import name 'splitattr' from 'urllib.request' (/usr/lib/python3.8/urllib/request.py)

Target(s) affected by this defect ?

n/a

Toolchain(s) (name and version) displaying this defect ?

n/a

What version of Mbed-os are you using (tag or sha) ?

master (d6784c3)

What version(s) of tools are you using. List all that apply (E.g. mbed-cli)

mbed-cli 1.10.5

How is this defect reproduced ?

Follow the steps below. Either run pip install -r requirements.txt or let mbed do it.

$ git reset --hard upstream/master
HEAD is now at d6784c3ee6 Update Mbed version block
$ virtualenv venv
created virtual environment CPython3.8.5.final.0-64 in 91ms
  creator CPython3Posix(dest=/home/filip/workspace/mbed-os/venv, clear=False, no_vcs_ignore=False, global=False)
  seeder FromAppData(download=False, pip=bundle, setuptools=bundle, wheel=bundle, via=copy, app_data_dir=/home/filip/.local/share/virtualenv)
    added seed packages: pip==20.3.1, setuptools==51.0.0, wheel==0.36.1
  activators BashActivator,CShellActivator,FishActivator,PowerShellActivator,PythonActivator,XonshActivator
$ source venv/bin/activate
$ pip install mbed-cli
$ mbed device-management --help
[mbed] Working path "/home/filip/workspace/mbed-os" (program)
[mbed] WARNING: Could not find mbed program in current path "/home/filip/workspace/mbed-os".
       You can fix this by calling "mbed new ." in the root of your program.
---
[mbed] Auto-installing missing Python modules (pyyaml, jsonschema, mbed_cloud_sdk, jinja2, mbed_ls, mbed_host_tests, mbed_greentea, pyelftools, manifest_tool, icetea, pycryptodome, pyusb, cmsis_pack_manager, psutil, cryptography, click, cbor)...
Traceback (most recent call last):
  File "/home/filip/workspace/mbed-os/tools/device_management.py", line 27, in <module>
    from manifesttool import create, parse, verify, cert, init, update
  File "/home/filip/workspace/mbed-os/venv/lib/python3.8/site-packages/manifesttool/create.py", line 19, in <module>
    from manifesttool.v1.create import main as create_v1
  File "/home/filip/workspace/mbed-os/venv/lib/python3.8/site-packages/manifesttool/v1/create.py", line 37, in <module>
    from manifesttool import utils, codec, errorhandler, defaults
  File "/home/filip/workspace/mbed-os/venv/lib/python3.8/site-packages/manifesttool/utils.py", line 32, in <module>
    from future.moves.urllib.request import urlopen, Request
  File "/home/filip/workspace/mbed-os/venv/lib/python3.8/site-packages/future/moves/urllib/request.py", line 9, in <module>
    from urllib.request import (getproxies,
ImportError: cannot import name 'splitattr' from 'urllib.request' (/usr/lib/python3.8/urllib/request.py)
[mbed] ERROR: "/home/filip/workspace/mbed-os/venv/bin/python" returned error.
       Code: 1
       Path: "/home/filip/workspace/mbed-os"
       Command: "/home/filip/workspace/mbed-os/venv/bin/python -u /home/filip/workspace/mbed-os/tools/device_management.py --help"
       Tip: You could retry the last command with "-v" flag for verbose output
---

[ciarmcom]

Thank you for raising this detailed GitHub issue. I am now notifying our internal issue triagers.
Internal Jira reference: https://jira.arm.com/browse/IOTOSM-2991