Emscripten build fails to import `importlib.metadata`

[ryanking13]

Emscripten build fails to import importlib.metadat becuase the email module is missing.

>>> import importlib.metadata
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/workspaces/cpython/Lib/importlib/metadata/__init__.py", line 14, in <module>
ModuleNotFoundError: No module named 'email'

email module is omitted [here], marked as a networking-related package.

cpython/Tools/wasm/emscripten/wasm_assets.py

Lines 60 to 61 in fc0305a

	OMIT_NETWORKING_FILES = (
	"email/",

But the email format is used for parsing the package metadata as well, so I think it is better to include it in emscripten builds.

Linked PRs

• gh-138515: Include email module in Emscripten build #138520
• [3.14] gh-138515: Include email module in Emscripten build (gh-138520) #138533
• [3.13] gh-138515: Include email module in Emscripten build (gh-138520) #138534

[uranusjr]

The email module is designed specifically to only manage email messages, more similar to urllib.parse than urllib.request. It’s a good idea to include it in the build IMO.