extmod/asyncio/uasyncio.py: Add backwards-compatible uasyncio alias.

This allows existing code that does `import uasyncio` or
`import uasyncio as asyncio` to continue working.

It uses the same lazy-loading as asyncio to prevent loading of unused
features.

This work was funded through GitHub Sponsors.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>

extmod/asyncio/uasyncio.py

@@ -0,0 +1,8 @@
+# This module just allows `import uasyncio` to work. It lazy-loads from
+# `asyncio` without duplicating its globals dict.
+
+
+def __getattr__(attr):
+    import asyncio
+
+    return getattr(asyncio, attr)