Write a program that asks the user for the name of file of addresses and a name of an output file

Question

Your program should replace all occurrences of "NY" with "New York," all occurrences of "NJ" with "New Jersey

For example, if your file replace.txt contains:

from wikipedia:
NY-NJ-CT Tri-State Area
The NY metropolitan area includes the most populous city in the US
(NY City); counties comprising Long Island and the Mid- and Lower Hudson 
Valley in the state of New York.

The output has to be:

from wikipedia:
New York-New Jersey-CT Tri-State Area
The New York metropolitan area includes the most populous city in the United 
States (New York City); counties comprising Long Island and the Mid- and 
Lower Hudson Valley in the state of New York.

I tried my best and here is my program.

filename = input("Please enter a file name: ")
openfile = open(filename, "r")
readfile = openfile.read()


for i in readfile:
    for string in i.replace("NY", "New York"):
        Replace = string.replace("NJ", "New Jersey")

print(Replace)

The problem is that it is not printing out anything. PLEASE HELP!

Answer 1

Just for replacing the two thinkgs, this is enough:

Replace = readfile.replace("NJ", "New Jersey")
Replace = Replace.replace("NY", "New York")

# or
# Replace = readfile.replace("NJ", "New Jersey").replace("NY", "New York")

print(Replace)

You dont need any for loops here. readfile already contains full contents of the input file.

To save the results in a new file:

with open("outfile.txt",'w') as f:
    f.write(Replace)

Answer 2

Something like:

for i in readfile:
    i = i.replace("NY", "New York")
    i = i.replace("NJ", "New Jersey")
    print (i)

But it's not quite correct, as you are reading the entire file into readfile. It's often better to process the file line by line

filename = input("Please enter a file name: ")
with open(filename, "r") as readfile:
    for i in readfile:
        i = i.replace("NY", "New York")
        i = i.replace("NJ", "New Jersey")
        print (i)