Fix incomplete format error in asdl.py
diff --git a/Parser/asdl.py b/Parser/asdl.py
index 7f5856b..1ddc3f8 100644
--- a/Parser/asdl.py
+++ b/Parser/asdl.py
@@ -126,7 +126,7 @@
         "version ::= Id String"
         if version.value != "version":
             raise ASDLSyntaxError(version.lineno,
-                                msg="expected 'version', found %" % version)
+                                msg="expected 'version', found %s" % version)
         return V
 
     def p_definition_0(self, (definition,)):
diff --git a/Parser/asdl_c.py b/Parser/asdl_c.py
index 3d46220..44c3a6d 100755
--- a/Parser/asdl_c.py
+++ b/Parser/asdl_c.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python2
 """Generate C code from an ASDL description."""
 
 # TO DO