I need to create a string of hex digits from a list of random integers (0-255). Each hex digit should be represented by two characters: 5 - \"05\", 16 - \"10\", etc.
a = [0,1,2,3,127,200,255] print str.join("", ("%02x" % i for i in a))
prints
000102037fc8ff
(Also note that your code will fail for integers in the range from 10 to 15.)