Need help placing info on a new line in a file

Question

im trying to create a database by using dictionaries. i convert the dictionary into a string once ive finished adding and deleting things from it but when i want to save the string, i would like the the keys to be on a new line from each other.

here is my code so far:

print('|-----Welcome to the Address Book-------|')
print('|----------------------------------------|')
print('|Please choice from the following:-------|')
print('|----------1: Find   Contact------------|')
print('|----------2: Add    Contact------------|')
print('|----------3: Delete Contact------------|')
print('|----------4: Quit Address Book----------|')

choice = [1, 2, 3, 4, 5]


document = open('addresses.txt', 'r+')
address = {}
for line in document:
    if line.strip():
        key, value = line.split(None, 1)
        address[key] = value.split()
document.close()
open('addresses.txt', 'w')

while 1:
    answer = 0
    while answer not in choice:
        try:
            answer = int(input("Enter here: "))
        except ValueError:
            0

    if answer == 1:
        x = input('Enter his/her name: ')
        if x in address:
            print("This is their address: ", address[x])
        else:
            print('Contact does not exist!')

    if answer == 2:
        x = (input('Enter new contact: '))
        x = x.replace(" ", "_")
        if x in address:
            while True:
                z = str(input('Contact '+x+' with address: '+str(address[x]) + ' already existed, do you want to override?(Yes/No)'))
                if z == 'yes':
                    b = input('Enter Address: ')
                    c = input('Enter postcode: ')
                    del address[x]
                    break

                elif z == 'no':
                    break
                else:
                    print('Please choose yes or no')

        else:
            b = input('Enter Address: ')
            c = input('Enter postcode: ')
        b = b.replace(" ", "_")
        c = c.replace(" ", "_")
        address[x] = b, c

    if answer == 3:
        z = input('Enter whom you would like to delete: ')
        if z in address:
            del address[z]
        else:
            print('Contact does not exist!')

    if answer == 4:
        a = "{}':(),[]"
        ok = str(address)

        for char in a:
            ok = ok.replace(char, "")

        document = open('addresses.txt', 'r+')
        document.write(ok + '\n')
        document.close()
        break

when saving to file, i would like to save each key and its info like this:

>Bob address postcode
>Sam address postcode

but instead it is saved like this:

>Bob address postcode Sam address postcode

Answer 1

When writing a dictionary to file, do the following:

with open('/file/path', 'w') as f:
    for k, v in d.items():
        f.write(k + v + "\n")

This assumes a few things:

1. You want to overwrite the file, not append; if you do, switch 'w' to 'a'
2. All the key and value items are str

Answer 2

I don't like using 'r+' . You should open(filename, "r") when you want to read from a file and open(filename, "w") when you want to read your file. In my opinion, it's way easier because while using 'r+' , you have to think about where the seek is (the blinking cursor that you see while writing/editing somewhere). For that you'll need something like:

file=open(filename,"r+")
file.seek(0)
file.write("something" + "\n")

Well, I don't really use the "r+" method very much so I can't explain anymore. I suggest that you read more about it in the docs.

Answer 3

If you print str(address) to your screen, you will understand why this happens. The str command converts everything (ie keys and values) to a concatanated string and that will be stored in your document file.

Instead you should save the items of your address book one by one, iterating over all persons.

ok = ""
for person in address:
    ok += person + " " + address[person] + "\n"

with open('addresses.txt', 'w') as file_out:
    file_out.write(ok)