Badger2040: Allow builtin demos to be replaced

.github/workflows/micropython-badger2040.yml

@@ -45,7 +45,7 @@ jobs:
     - name: Copy modules & examples
       run: |
         cp -r pimoroni-pico-${GITHUB_SHA}/micropython/badger2040_modules_py/* micropython/ports/rp2/modules/
-        cp pimoroni-pico-${GITHUB_SHA}/micropython/examples/badger2040/launcher.py micropython/ports/rp2/modules/
+        cp pimoroni-pico-${GITHUB_SHA}/micropython/examples/badger2040/launcher.py micropython/ports/rp2/modules/_launcher.py
         cp pimoroni-pico-${GITHUB_SHA}/micropython/examples/badger2040/clock.py micropython/ports/rp2/modules/_clock.py
         cp pimoroni-pico-${GITHUB_SHA}/micropython/examples/badger2040/fonts.py micropython/ports/rp2/modules/_fonts.py
         cp pimoroni-pico-${GITHUB_SHA}/micropython/examples/badger2040/e-reader.py micropython/ports/rp2/modules/_ebook.py

micropython/badger2040_modules_py/boot.py

@@ -1,19 +1,6 @@
-#import gc
-#import machine
-#
-#a = machine.Pin(12, machine.Pin.IN, machine.Pin.PULL_DOWN)
-#b = machine.Pin(13, machine.Pin.IN, machine.Pin.PULL_DOWN)
-#c = machine.Pin(14, machine.Pin.IN, machine.Pin.PULL_DOWN)
-#
-#if a.value() or b.value() or c.value():
-#    for k in locals().keys():
-#        if k not in ("gc"):
-#            del locals()[k]
-#    gc.collect()
-#    __import__("launcher.py")
 try:
     open("main.py", "r")
 except OSError:
     with open("main.py", "w") as f:
-        f.write("import launcher")
+        f.write("import _launcher")
         f.flush()

micropython/examples/badger2040/launcher.py

@@ -171,7 +171,10 @@ def launch(file):
         if k not in ("gc", "file"):
             del locals()[k]
     gc.collect()
-    __import__(file)
+    try:
+        __import__(file[1:])  # Try to import _[file] (drop underscore prefix)
+    except ImportError:
+        __import__(file)      # Failover to importing [_file]
     sys.exit(0)