# a global dictionary to store post codes
postcodes = {}

def readcodes(filename):
	''' Read post codes from <filename> and store in the global variable <postcodes> '''
	global postcodes
	# read the file and split them by lines
	pcs = open(filename, 'rU').read().split('\n')

	# split each line by a colon (":"), allowing 1 split max
	postcodes = dict( [ pc.strip().split(':', 1) for pc in pcs if pc.strip() ] )

def lookupcode(code):
	return postcodes.get(code, 'Unknown')