Issue #28998: More APIs now support longs as well as ints.
diff --git a/Lib/compiler/pyassem.py b/Lib/compiler/pyassem.py
index f52f7d0..b82073e 100644
--- a/Lib/compiler/pyassem.py
+++ b/Lib/compiler/pyassem.py
@@ -581,7 +581,7 @@
 
 def twobyte(val):
     """Convert an int argument into high and low bytes"""
-    assert isinstance(val, int)
+    assert isinstance(val, (int, long))
     return divmod(val, 256)
 
 class LineAddrTable: