我知道这与换行标记有关，但是为什么我的程序在我的外部文件中找不到用户名/密码匹配？

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()