Patch #1181: add os.environ.clear() method.
diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index 7f03a75..24830d2 100644
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -115,9 +115,13 @@
    passed to the appropriate process-creation functions to cause  child processes
    to use a modified environment.
 
-   If the platform supports the :func:`unsetenv` function, you can  delete items in
+   If the platform supports the :func:`unsetenv` function, you can delete items in
    this mapping to unset environment variables. :func:`unsetenv` will be called
-   automatically when an item is deleted from ``os.environ``.
+   automatically when an item is deleted from ``os.environ``, and when
+   :meth:`os.environ.clear` is called.
+
+   .. versionchanged:: 2.6
+      Also unset environment variables when calling :meth:`os.environ.clear`.
 
 
 .. function:: chdir(path)