fix typo; thanks to Justin Watt from docs@
diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
index d2949f6..bdf07a4 100644
--- a/Doc/library/unittest.rst
+++ b/Doc/library/unittest.rst
@@ -376,7 +376,7 @@
widget = Widget('The widget')
self.assertEqual(widget.size(), (50, 50), 'incorrect default size')
-Note that in order to test something, we use the one of the :meth:`assert\*`
+Note that in order to test something, we use one of the :meth:`assert\*`
methods provided by the :class:`TestCase` base class. If the test fails, an
exception will be raised, and :mod:`unittest` will identify the test case as a
:dfn:`failure`. Any other exceptions will be treated as :dfn:`errors`. This