used f-string (#32133)

Author: PSY27

doc/source/user_guide/io.rst

@@ -3815,7 +3815,7 @@ The right-hand side of the sub-expression (after a comparison operator) can be:
    .. code-block:: ipython
 
       string = "HolyMoly'"
-      store.select('df', 'index == %s' % string)
+      store.select('df', f'index == {string}')
 
    The latter will **not** work and will raise a ``SyntaxError``.Note that
    there's a single quote followed by a double quote in the ``string``