Test changes to Actually Portable Python (#240)

- Add missing `os.pipe` and `os.getuid`
- Commented out _dummy_thread from Lib/threading.py so tests
  don't simulate multi-threading and waste time/error out
- Revert test_hashlib to avoid blake2

third_party/python/Lib/test/test_code.py

@@ -104,7 +104,10 @@ consts: ('None',)
 
 import inspect
 import sys
-import threading
+try:
+    import threading
+except ImportError as e:
+    threading = None
 import unittest
 import weakref
 try: