Ensure that functools.wraps is not called on functools.partial objects in rev_block.

PiperOrigin-RevId: 209524010

tensorflow/contrib/layers/python/layers/rev_block_lib.py

@@ -151,9 +151,19 @@ def _rev_block_forward(x1,
   return y1, y2
 
 
+def _safe_wraps(fn):
+  if isinstance(fn, functools.partial):
+    # functools.partial objects cannot be wrapped as they are missing the
+    # necessary properties (__name__, __module__, __doc__).
+    def passthrough(f):
+      return f
+    return passthrough
+  return functools.wraps(fn)
+
+
 def _scope_wrap(fn, scope):
 
-  @functools.wraps(fn)
+  @_safe_wraps(fn)
   def wrap(*args, **kwargs):
     with variable_scope.variable_scope(scope, use_resource=True):
       return fn(*args, **kwargs)
@@ -430,7 +440,7 @@ def rev_block(x1,
 def enable_with_args(dec):
   """A decorator for decorators to enable their usage with or without args."""
 
-  @functools.wraps(dec)
+  @_safe_wraps(dec)
   def new_dec(*args, **kwargs):
     if len(args) == 1 and not kwargs and callable(args[0]):
       # Used as decorator without args
@@ -477,7 +487,7 @@ def recompute_grad(fn, use_data_dep=_USE_DEFAULT, tupleize_grads=False):
     tf.gradients).
   """
 
-  @functools.wraps(fn)
+  @_safe_wraps(fn)
   def wrapped(*args):
     return _recompute_grad(
         fn, args, use_data_dep=use_data_dep, tupleize_grads=tupleize_grads)