exp.py

#! /usr/bin/python3

import json
pwds = dict()
# get passphrase from user
try:
    fp = open("passwords.dat","rb")
    try:
        # decrypt here.
        # passwords is the decrypted content
        pwds = json.loads(passwords)
        
    except:
        ## exit (probably because passphrase is wrong)
    fp.close()
except:
    fp = open("passwords.dat","w")
    fp.close()


while True:
    choice = input("Enter command:  A to add password, V to view passwords, Q to quit:\n")
    if choice  == 'A':
        site = input("which site? ")
        pwds[site] = input("which password? ")
    if choice == 'V':
        for k in pwds:
            print("password to {} is {}.".format(k,pwds[k]))
    if choice == 'Q':
        break
fp = open("passwords.json","w")
json.dump(pwds,fp)
fp.close()