Change 'lowered' to 'lowercased'

Doc/library/stdtypes.rst

@@ -967,7 +967,7 @@ functions based on regular expressions.
 .. method:: str.capitalize()
 
    Return a copy of the string with its first character capitalized and the
-   rest lowered.
+   rest lowercased.
 
 
 .. method:: str.center(width[, fillchar])