Python - matching data from an external file (username password)

Question

I know it's something to do with the newline tag, but why can't my program find a username/password match in my external file?

username = input("Please enter your username: ")
password = input("Please enter your password: ")
file = open("UsernamesPasswords.txt", "r")
for loop in file:
    line = file.readline()
    data = line.split(",")
    print(data)
    if username == data[0] and password == data[1]:
        print("That's a match")
    else:
        print("That's not a match!")
        break
file.close()

Answer 1

Assuming that the UsernamesPasswords.txt looks like this:

username_1,password_1
username_2,password_2
username_3,password_3

We can write the code:

username_input = input("Please enter your username: ")
password_input = input("Please enter your password: ")
file = open("UsernamesPasswords.txt", "r")
contents = file.read()
file.close()

for line_index, line in enumerate(contents.splitlines()):
    parts = line.strip().split(",")

    if len(parts) != 2:
        # Incorrect line
        continue

    username, password = parts

    if username == username_input and password == password_input:
        print(f"That's a match, at line {line_index}.")
    else:
        print(f"That's not a match, at line {line_index}.")
        break