diff --git a/Lib/runpy.py b/Lib/runpy.py
index 4738df3..496df6d 100644
--- a/Lib/runpy.py
+++ b/Lib/runpy.py
@@ -226,7 +226,7 @@
         code = read_code(f)
     if code is None:
         # That didn't work, so try it as normal source code
-        with open(fname, "rU") as f:
+        with open(fname, "r") as f:
             code = compile(f.read(), fname, 'exec')
     return code