def login():

    UserName = input("Inany da Silva Serra: ")

    passw = input("Search the password: ")

    check(Inany, passw)

    return UserName, passw

def check(Inany, password):

    pword = {}

    for line in open('unames_passwords.txt','r'):

        user, password = line.split()

        pword\[user\] = password

        if user == UserName and password == passw:

           return True

           print("Thank you for logging in.")

        else:

           print("Username or password is incorrect")

def main():

    login()

main()