> > x = [0010, 0210] > > You do realize that this is octal, right? It's unfortunate I choose that, the numbers go beyond octal > len is undefined for integers. Perhaps you meant "len(str(x[1]))". Yes sorry it was late at night :P > You can, however, do this: > >>> '%0*d' % (5, 123) > '00123' This is exactly what I needed Thank-you kindly