Changes in anticipation of stricter str vs. bytes enforcement.
diff --git a/Lib/uu.py b/Lib/uu.py
index 084d9f3..18a9f79 100755
--- a/Lib/uu.py
+++ b/Lib/uu.py
@@ -72,12 +72,12 @@
     #
     # Write the data
     #
-    out_file.write('begin %o %s\n' % ((mode & 0o777),name))
+    out_file.write(('begin %o %s\n' % ((mode & 0o777), name)).encode("ascii"))
     data = in_file.read(45)
     while len(data) > 0:
-        out_file.write(str(binascii.b2a_uu(data), "ascii"))
+        out_file.write(binascii.b2a_uu(data))
         data = in_file.read(45)
-    out_file.write(' \nend\n')
+    out_file.write(b' \nend\n')
 
 
 def decode(in_file, out_file=None, mode=None, quiet=0):