gh-106318: Add examples for str.replace() method

Author: adorilson

Doc/library/stdtypes.rst

@@ -2398,17 +2398,19 @@ expression support in the :mod:`re` module).
    Return a copy of the string with all occurrences of substring *old* replaced by
    *new*.  If *count* is given, only the first *count* occurrences are replaced.
    If *count* is not specified or ``-1``, then all occurrences are replaced.
+   For example:
 
-   .. versionchanged:: 3.13
-      *count* is now supported as a keyword argument.
-
-   For example::
+   .. doctest::
 
       >>> 'spam, spam, spam'.replace('spam', 'eggs')
       'eggs, eggs, eggs'
       >>> 'spam, spam, spam'.replace('spam', 'eggs', 1)
       'eggs, spam, spam'
 
+   .. versionchanged:: 3.13
+      *count* is now supported as a keyword argument.
+
+
 .. method:: str.rfind(sub[, start[, end]])
 
    Return the highest index in the string where substring *sub* is found, such