add translate_enfr_wmt32k_packed problem.

PiperOrigin-RevId: 177752030

Author: nshazeer

Diff for: tensor2tensor/data_generators/translate_enfr.py

@@ -143,6 +143,14 @@ def use_small_dataset(self):
     return False
 
 
+@registry.register_problem
+class TranslateEnfrWmt32kPacked(TranslateEnfrWmt32k):
+
+  @property
+  def packed_length(self):
+    return 256
+
+
 @registry.register_problem
 class TranslateEnfrWmtSmallCharacters(translate.TranslateProblem):
   """Problem spec for WMT En-Fr translation."""