#
# Original homework solution
#

def ask_user():
	import sys
	sys.stdout.write("Enter ZIP code: ")
	zipcode = sys.stdin.readline().strip()
	# Should check for valid zip code here
	town, population = find_zip(zipcode)
	print "%s -> %s (population %s)" % (zipcode, town, population)

def find_zip(zipcode):
	import urllib
	conn = urllib.urlopen("http://www.uszip.com/zip/%s" % zipcode)
	town = "unknown"
	population = "unknown"
	for line in conn.fp:
		if "is the zip code of " in line:
			town = get_town(line)
		elif "Population:" in line:
			population = get_population(line)
	return town, population

def get_town(line):
	line = strip_tags(line)
	key_string = "is the zip code of "
	try:
		n = line.index(key_string)
	except ValueError:
		return "unknown"
	else:
		return line[n + len(key_string):]

def get_population(line):
	line = strip_tags(line)
	key_string = "Population:"
	try:
		n = line.index(key_string)
	except ValueError:
		return "unknown"
	else:
		start = n + len(key_string)
		stop = start + 1
		while stop < len(line):
			if line[stop] not in "0123456789,":
				break
			stop += 1
		return line[start:stop]

def strip_tags(line):
	keep = []
	in_tag = False
	for c in line:
		if in_tag:
			if c == '>':
				in_tag = False
		else:
			if c == '<':
				in_tag = True
			else:
				keep.append(c)
	return ''.join(keep).strip()

ask_user()