encoding control characters

[Skaperen]

has anyone seen code to encode control characters? here is my code to decode control characters. encode is Carriage Return -> '\r', decode is '\r' -> Carriage Return.

from __future__ import division, generators, print_function, with_statement
#-------#-------#-------#-------#-------#-------#-------#-------#-------#-------#
# -*- coding: utf-8 -*-
# file          decodecontrol.pyf
# purpose       function to decode control characters
# email         10054452614123394844460370234029112340408691
# function      decode_control
#
# purpose       decode character sequences that encode other characters like
#               control characters that are not readily entered in a plain
#               character string.
#
# 1 argument    string with encoded control characters - ascii
#
# returns       tuple (unprocessed count,decoded result string,end char)
#
# codes               ^a or \001 or \x01 = {1} Ctrl-A
#                     ^b or \002 or \x02 = {2} Ctrl-B
#               \c or ^c or \003 or \x03 = {3} Ctrl-C
#                     ^d or \004 or \x04 = {4} Ctrl-D
#                     ^e or \005 or \x05 = {5} Ctrl-E
#                     ^f or \006 or \x06 = {6} Ctrl-F
#               \a or ^g or \007 or \x07 = {7} Alarm
#               \b or ^h or \010 or \x08 = {8} Backspace
#               \t or ^i or \011 or \x09 = {9} Tab
#               \n or ^j or \012 or \x0a = {10} Newline
#               \v or ^k or \013 or \x0b = {11} Vertical Tab
#               \f or ^l or \014 or \x0c = {12} Formfeed
#               \r or ^m or \015 or \x0d = {13} Carriage Return
#               \e or ^[ or \033 or \x1b = {27} Escape
#               \\       or \134 or \x5c = {92} literal backslash
#               \^       or \136 or \x5e = {94} literal carat
#                     ^@ or \0   or \x00 = {0} raw binary zero
#               \[0-3][0-7][0-7]         converts octal to raw
#               \x[0-9a-fA-F][0-9a-fA-F] converts cetal to raw
#               \o[0-7][0-7][0-7]        converts octal to raw
#               \d[0-2][0-9][0-9]        converts decimal to raw
#
# note          only 8 bits is used for bytes encoded with the \d sequence
#               for any value given in the 3 digits it interprets.
#-------#-------#-------#-------#-------#-------#-------#-------#-------#-------#
def decode_control(istr):
    code = {'a':7,'b':8,'c':3,'t':9,'n':10,'v':11,'f':12,'r':13,'z':26,'e':27,'\\':92,'^':94}
    base = {'d':(3,10),'o':(3,8),'x':(2,16)}
    l = len(istr)
    ostr = ''
    while istr:
        c = istr[0]
        istr = istr[1:]
        l = len(istr)
        if c == '^':
            if l < 1:
                return l,ostr,c
            c,istr,l = chr(ord(istr[0])%32),istr[1:],l-1
        elif c == '\\':
            if l < 1:
                return l,ostr,c
            c,istr,l = istr[0].lower(),istr[1:],l-1
            if c in code:
                c = chr(code[c])
            elif c in ('0','1','2','3'):
                c = None
                try:
                    for x in range(3,6):
                        c = int(istr[2:x],8)
                except ValueError:
                    if c is None:
                        return l,ostr,c
            elif c in base:
                if l < 2:
                    return l,ostr,c
                d,b = base[c]
                try:
                    digits = istr[1:2+d]
                    c = int(istr[1:2+d],b) & 255
                except ValueError:
                    return l,ostr,c
            else:
                return l,ostr,c
        ostr += c
    return l,ostr,None
# EOF