No module named '__builtin__' in Ubuntu 20.04 (Canonical image)

Describe the bug

I was trying to install the OmsAgentForLinux and enablevmaccess extensions in Ubuntu 20.04 via CLI.

Command Name az vm extension image list

Errors:

No module named '__builtin__'
Traceback (most recent call last):
python3/dist-packages/knack/cli.py, ln 206, in invoke
    cmd_result = self.invocation.execute(args)
cli/core/commands/__init__.py, ln 528, in execute
    self.commands_loader.load_arguments(command)
azure/cli/core/__init__.py, ln 300, in load_arguments
    loader.load_arguments(command)  # this adds entries to the argument registries
cli/command_modules/vm/__init__.py, ln 31, in load_arguments
    from azure.cli.command_modules.vm._params import load_arguments
...
dist-packages/antlr4/error/Errors.py, ln 5, in <module>
    from antlr4.atn.Transition import PredicateTransition
dist-packages/antlr4/atn/Transition.py, ln 19, in <module>
    from __builtin__ import unicode
ModuleNotFoundError: No module named '__builtin__'

To Reproduce:

Steps to reproduce the behavior. Tried any and all of the following:

• sudo apt install azure-cli
  • “/usr/lib/python3/dist-packages/azure/cosmos/session.py:186: SyntaxWarning: “is not” with a literal. Did you mean “!=”? if session_token is not ‘’:”
  • …
• az vm extension image list --location eastus --output table
  • “ModuleNotFoundError: No module named ‘antlr4’”
• sudo apt install python3-pip
• sudo pip3 install antlr4-python2-runtime
• az vm extension image list --location westus --output table
  • “ModuleNotFoundError: No module named ‘__builtin__’”
• pip3 install future
• az vm extension image list --location westus --output table
  • “ModuleNotFoundError: No module named ‘__builtin__’”
• Rinse, repeat

Expected Behavior

• It would be nice if Azure supported backups of Ubuntu 20.04
• It would be nice if the CLI worked in Ubuntu 20.04

Environment Summary

Linux-5.4.0-1010-azure-x86_64-with-glibc2.29
Python 3.8.2
Shell: bash

azure-cli 2.0.81 *

Extensions:
azure-devops 0.17.0

Additional Context

I installed Ubuntu 20.04 from a public image (Ubuntu Server 20.04 LTS - Canonical) since there appears to be no official one (?), but when I tried to enable backups, I keep getting:

Could not communicate with the VM agent for snapshot status - Snapshot VM sub task timed out

Looking under Extensions in Portal, it says “OmsAgentForLinux (unavailable)”. It seems that I have no resort but to create a new instance with 18.04 and reproduce the tedium of re-configuring and migrating everything, but I thought that I would share this failure because the CLI recommended az feedback. I tried using the CLI to install the missing extensions (since they are inexplicably absent when I click “Add” extension from Portal).

I imagine that this will be #wontfix’d as a Canonical or Python issue, but here it is for posterity.

• I am not an expert of the following: Azure, Python, azure-cli
• I imagine that switching to Python 2 might have an impact, but I have run out of time trying to get the CLI to work.

EDIT: Repeating these steps with Python 2 yielded the same errors, and now it is recommending that I retry on Saturday:

[jkendzorra]

Here’s a workaround for those willing to use pip3: sudo pip3 install antlr4-python3-runtime (from https://golder.org/azure-cli-cant-find-antlr4-python-library/)

[fengzhou-msft]

The azure-cli package that comes with the Focal universe repo is a bit old and has some issues. A new Focal package is just released for azure-cli 2.6.0. Please follow https://docs.microsoft.com/en-us/cli/azure/install-azure-cli-apt?view=azure-cli-latest to try again.