String to int and back.

string_to_int.py

import math


def string_to_int(string):
    """Convert a string to the equivalent integer."""
    # For each character, convert to an integer, convert that to hex,
    # remove the first two chars ("0x") and left-pad with a zero.
    hexchars = [hex(ord(x))[2:].rjust(2, "0") for x in string]
    return int("".join(hexchars), 16)


def int_to_string(integer):
    """Convert an integer back to the equivalent string."""
    hexstring = hex(integer)[2:].rstrip("L")
    # Pad the hexstring with zeros to the left to get an even
    # number of digits.
    padded = hexstring.rjust(int(math.ceil(len(hexstring) / 2.0) * 2), "0")
    stringlist = []
    for counter in range(0, len(padded), 2):
        # Convert every pair of two hex digits into a char.
        charpair = padded[counter:counter + 2]
        char = chr(int("0x" + charpair, 16))
        stringlist.append(char)
    return "".join(stringlist)