Force document private methods/functions

PiperOrigin-RevId: 338486134
Change-Id: I62efc520652e6db7d5f84cbfc55a6def48f5be4f

tensorflow/tools/docs/doc_controls.py

@@ -250,3 +250,34 @@ def for_subclass_implementers(obj):
 
 
 do_not_doc_in_subclasses = for_subclass_implementers
+
+_DOC_PRIVATE = "_tf_docs_doc_private"
+
+
+def doc_private(obj):
+  """A decorator: Generates docs for private methods/functions.
+
+  For example:
+
+  ```
+  class Try:
+
+    @doc_controls.doc_private
+    def _private(self):
+      ...
+  ```
+
+  As a rule of thumb, private(beginning with `_`) methods/functions are
+  not documented.
+
+  This decorator allows to force document a private method/function.
+
+  Args:
+    obj: The class-attribute to hide from the generated docs.
+
+  Returns:
+    obj
+  """
+
+  setattr(obj, _DOC_PRIVATE, None)
+  return obj