Fix build and delete superfluous files

- Make Python make formatting pristine
- Add missing `#pragma weak` to Python source
- Fix Clang script flake due to missing directory

test/libc/release/clang.sh

@@ -3,6 +3,7 @@
 #───vi: set net ft=sh ts=2 sts=2 fenc=utf-8 :vi─────────────┘
 
 if CLANG=$(command -v clang); then
+  mkdir -p o/$MODE/test/libc/release
   $CLANG                                              \
       -o o/$MODE/test/libc/release/smokeclang.com.dbg \
       -Os                                             \

test/libc/release/lld.sh

@@ -5,6 +5,7 @@
 # TODO(jart): implement me
 
 if CLANG=$(command -v clang); then
+  mkdir -p o/$MODE/test/libc/release
   $CLANG                                              \
       -o o/$MODE/test/libc/release/smokeclang.com.dbg \
       -Os                                             \

test/libc/release/metal.sh

@@ -8,6 +8,8 @@ if [ "$MODE" = opt ]; then
   exit
 fi
 
+mkdir -p o/$MODE/test/libc/release/
+
 # smoke test booting on bare metal and printing data to serial uart
 CMD="o/$MODE/tool/build/blinkenlights.com.dbg -r o/$MODE/examples/hello.com"
 if OUTPUT="$($CMD)"; then