unittest.mock does not work on WebAssembly build of CPython

[treyhunner]

Bug report

Use CPython compiled for WebAssembly and then import unittest.mock

Or visit this page and click the "Run in Browser" button to see the error.

The error shown is:

Traceback (most recent call last):
  File "//__main__.py", line 2, in <module>
    import unittest.mock
  File "/home/runner/work/cpython-wasm-test/cpython-wasm-test/cpython/Lib/unittest/mock.py", line 26, in <module>
  File "/home/runner/work/cpython-wasm-test/cpython-wasm-test/cpython/Lib/asyncio/__init__.py", line 8, in <module>
  File "/home/runner/work/cpython-wasm-test/cpython-wasm-test/cpython/Lib/asyncio/base_events.py", line 18, in <module>
ModuleNotFoundError: No module named 'concurrent'

This error seems to only occur on the WebAssembly build for the browser (the Node build allows unittest.mock to be imported as expected).

Your environment

• CPython versions tested on: 3.11.0rc2
• Operating system and architecture: WebAssembly

[brettcannon]

@tiran can this issue be closed?

[treyhunner]

Closing, as unittest.mock works for me now