Checking cleanup.

build.py

@@ -350,13 +350,12 @@ class Generator():
         
         if hasattr(args[0], 'held_object'):
             exe = args[0].held_object
-            if not isinstance(exe, Executable):
-                raise InvalidArguments('First generator argument must be an executable.')
         elif hasattr(args[0], 'ep'):
             exe = args[0].ep
         else:
-            print(args[0])
             raise InvalidArguments('First generator argument must be an executable object.')
+        if not isinstance(exe, Executable):
+            raise InvalidArguments('First generator argument must be an executable.')
         self.exe = exe
         self.process_kwargs(kwargs)