Add tests, comment what's up with change..

and use isinstance()

test/simple_source/bug24/02_loop_continue_dead_code.py

@@ -0,0 +1,18 @@
+"""This program is self-checking!"""
+# Python 2.4 - 2.7 bug in transforming "else if" to "elif" in Python 2.4 .. 2.7
+# From Issue #377
+
+# RUNNABLE!
+def loop_continue_dead_code(slots):
+    for name in slots:
+        if name:
+            pass
+        else:
+            continue
+            # The below is dead code
+            if x:
+                y()
+            else:
+                z()
+
+loop_continue_dead_code([None, 1])