  is the position in str to begin looking for one of 
              the characters in chars.  start may range from 0
              to n-1, where n is the number of characters in str.
 </PRE>
<h4><a name="Detailed_Output">Detailed_Output</a></h4>
<PRE>
 
   The function returns the index of the last character of str (at or
   before index start) that is one of the characters in the string
   chars.  The returned value normally ranges from 0 to n-1, where n is
   the number of characters in str. If none of th