grammatical fix; thanks to Alex Rudnick from docs@
diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst
index 73d454e..ada2d73 100644
--- a/Doc/library/argparse.rst
+++ b/Doc/library/argparse.rst
@@ -1116,7 +1116,7 @@
metavar
^^^^^^^
-When :class:`ArgumentParser` generates help messages, it need some way to refer
+When :class:`ArgumentParser` generates help messages, it needs some way to refer
to each expected argument. By default, ArgumentParser objects use the dest_
value as the "name" of each object. By default, for positional argument
actions, the dest_ value is used directly, and for optional argument actions,