Make tf2.enabled() available in the __internal__ namespace.

PiperOrigin-RevId: 338765979
Change-Id: Ifa8bbd78f468e0443de38fb4391e831e235e31f3

tensorflow/python/tf2.py

@@ -24,24 +24,27 @@ from __future__ import print_function
 
 import os
 
+from tensorflow.python.util.tf_export import tf_export
+
+
 _force_enable = None
 
 
 def enable():
-  #Enables v2 behaviors.
+  # Enables v2 behaviors.
   global _force_enable
   _force_enable = True
 
 
 def disable():
-  #Disables v2 behaviors.
+  # Disables v2 behaviors.
   global _force_enable
   _force_enable = False
 
 
+@tf_export("__internal__.tf2.enabled", v1=[])
 def enabled():
-  #Returns True iff TensorFlow 2.0 behavior should be enabled.
+  # Returns True iff TensorFlow 2.0 behavior should be enabled.
   if _force_enable is None:
     return os.getenv("TF2_BEHAVIOR", "0") != "0"
-
   return _force_enable

tensorflow/python/tools/api/generator/api_init_files.bzl

@@ -11,6 +11,7 @@ TENSORFLOW_API_INIT_FILES = [
     "__internal__/distribute/multi_process_runner/__init__.py",
     "__internal__/test/__init__.py",
     "__internal__/test/combinations/__init__.py",
+    "__internal__/tf2/__init__.py",
     "__internal__/tracking/__init__.py",
     "__operators__/__init__.py",
     "audio/__init__.py",

tensorflow/tools/api/golden/v2/tensorflow.__internal__.pbtxt

@@ -16,6 +16,10 @@ tf_module {
     name: "test"
     mtype: "<type \'module\'>"
   }
+  member {
+    name: "tf2"
+    mtype: "<type \'module\'>"
+  }
   member {
     name: "tracking"
     mtype: "<type \'module\'>"

tensorflow/tools/api/golden/v2/tensorflow.__internal__.tf2.pbtxt

@@ -0,0 +1,7 @@
+path: "tensorflow.__internal__.tf2"
+tf_module {
+  member_method {
+    name: "enabled"
+    argspec: "args=[], varargs=None, keywords=None, defaults=None"
+  }
+}