improve start default for relpath
diff --git a/Doc/library/os.path.rst b/Doc/library/os.path.rst
index 3771ab0..6b3a3b6 100644
--- a/Doc/library/os.path.rst
+++ b/Doc/library/os.path.rst
@@ -242,7 +242,7 @@
links encountered in the path (if they are supported by the operating system).
-.. function:: relpath(path, start=None)
+.. function:: relpath(path, start=os.curdir)
Return a relative filepath to *path* either from the current directory or
from an optional *start* directory. This is a path computation: the