"""

retVal = payload

if payload:

retVal = ""

i = 0

while i < len(payload):

if payload[i] == '%' and (i < len(payload) - 2) and payload[i + 1:i + 2] in string.hexdigits and payload[i + 2:i + 3] in string.hexdigits:

retVal += '%%25%s' % payload[i + 1:i + 3]

i += 3

else:

retVal += '%%25%.2X' % ord(payload[i])

i += 1