Replace keywords in string from dict

dict_rep.py

import re

ifile = open("smybol.txt, "r")
data = ifile.read()
ifile.close()

map = {}
map["DEVICE"] = "Resistor"
map["VALUE"] = "10k"

res = re.sub("\$(\w+)", lambda m: map[m.group(1)] if m.group(1) in map else m.group(0), data)
print res