how to map python 2.0 string opeartion to python 1.5.2 ?

[ed_tsang at yahoo.com]

Is there a way to map the following lines to 1.5.2?
I amusing 1.5.2 not the sys admin won;t upgrade to 2.0. I got a 
scirpt written for 2.0 and try to port it back to 1.5.2 ..


Code:

                   [fromValue, toValue] = line.split(delimiter)[:2] # 
Split line
        replaced by:           
                   [fromValue, toValue] = string.split(line,delimiter)

       .......
No idea how to replace these lines with 1.5.2 syntax:  
           if caseInsensitive:
                #    charMap[ord(fromValue.upper())] = toValue
                #    charMap[ord(fromValue.lower())] = toValue
replaced by:
		I don't know ...             
                # self.charMap = "".join(charMap)
replaced by:            
   	      self.charMap = string.join("",charMap)
 ............
       if not wholeWords:
            # rePattern = '|'.join(map(re.escape, fromVals))
replaced by:  
		rePattern = string.join('|', map(re.escape,fromVals))
        else:
            # rePattern = r'\b(' + '|'.join(map(re.escape, fromVals)) 
+ r')\b'
replaced by:
            temp = string.join('|', map(re.escape,fromVals))
            temp = string.join(temp,r')\b')
            rePattern = string.join(r'\b(',temp) --- ???
Tahnks