import pickle

email = {'John':'John_Email@gmail.com', 'Sara':'Sara_Email@gmail.com', 'Harry':'Harry_Email@gmail.com'}

file_mail = open('email.dat','wb')

email = pickle.load(file_mail)
file_mail.close()

print(email)
count = 0

while count == 0:
    print('Add an email address: 1')
    print('Modify an email address: 2')
    print('Delete an email address: 3')
    print('Display a list: 4')

choice = input('Enter a number from the list above:')

if int(choice)== 1:
    name = input('Enter name:')
    mail = input('Enter e-mail address:')
    email[name] = mail
    print('Added Successfully')

    if int(choice) == 2:
        name = input('Enter name:')
        mail = input('Enter e-mail address:')
        email[name] = mail
        print('Modified Successfully')

        if int(choice) == 3:
            name = input('Enter name:')
            mail = input('Enter e-mail address:')
            email[name] = mail
            print('Deleted Successfully')

            if int(choice) == 4:
                print(email)

else:
    print('Invalid Choice')
    c = input('Do you want to continue y/n: ')

    if c.upper() == 'N':
        count = 1
        print('Invalid Letter')
        file_mail = open('email.dat','wb')
        pickle.dump(email,file_mail)
        file_mail.close()