Anthony D'Agostino, this is my first raw version, it can fail in lots of ways depending on your input list l (and surely there are better ways to do it), but it's a start:
. l = [('A','Y'), ('J','A'), ('Y','J')] . pairs = dict(l) . result = [] . key = pairs.iterkeys().next() . while pairs: . val = pairs.pop(key) . result.append( (key, val) ) . key = val . print result Bear hugs, Bearophie -- http://mail.python.org/mailman/listinfo/python-list