puzzle4.py

import numpy as np
import sys

"""
Required fields:
    byr (Birth Year)
    iyr (Issue Year)
    eyr (Expiration Year)
    hgt (Height)
    hcl (Hair Color)
    ecl (Eye Color)
    pid (Passport ID)
    cid (Country ID) - optional

Example:

ecl:gry pid:860033327 eyr:2020 hcl:#fffffd
byr:1937 iyr:2017 cid:147 hgt:183cm

iyr:2013 ecl:amb cid:350 eyr:2023 pid:028048884
hcl:#cfa07d byr:1929

hcl:#ae17e1 iyr:2013
eyr:2024
ecl:brn pid:760753108 byr:1931
hgt:179cm

hcl:#cfa07d eyr:2025 pid:166559648
iyr:2011 ecl:brn hgt:59in

Count the number of valid passports - those that have all required fields. 
Treat cid as optional. In your batch file, how many passports are valid?
"""

def check_passport(passport):
    cnt=1
    fields = ['byr','iyr','eyr','hgt','hcl','ecl','pid','cid']
    f = []
    for line in passport:
        splt = line.split(' ')
        for entry in splt:
            f.append(entry.split(':')[0])
    #print(f)
    for flds in fields:
        if flds not in f and flds != 'cid':
            #print(flds, "passport not valid")
            cnt=0
    return cnt


with open('day4.in','r') as infile:
	lines = infile.readlines()

counter = 0
passport = []
for i in range(len(lines)):
    line = lines[i]
    if line == '\n':
        #print('----new passport')
        #print(passport)
        cnt = check_passport(passport)
        counter += cnt
        passport = []
    else:
        passport.append(line)

    if i==len(lines)-1:
        #print('----new passport')
        #print(passport)
        cnt = check_passport(passport)
        counter += cnt

print("Nr of valid passports:", counter)