diff --git a/Doc/library/2to3.rst b/Doc/library/2to3.rst
index d9eb00c..20a6245 100644
--- a/Doc/library/2to3.rst
+++ b/Doc/library/2to3.rst
@@ -122,7 +122,8 @@
 
 .. 2to3fixer:: callable
 
-   Converts ``callable(x)`` to ``hasattr(x, "__call_")``.
+   Converts ``callable(x)`` to ``isinstance(x, collections.Callable)``, adding
+   an import to :mod:`collections` if needed.
 
 .. 2to3fixer:: dict