Advanced Login System - Python 3.4

import sqlite3
from hashlib import md5

class Login():

    def __init__(self, database = "logins.db"):
        self.db = sqlite3.connect(database)
        self.sql = self.db.cursor()

        self.sql.execute("CREATE TABLE IF NOT EXISTS logins (username TEXT, password TEXT);")

    def new_user(self, username, password):
        self.sql.execute("INSERT INTO logins (username, password) VALUES (?, ?);",
                         (username, md5(password.encode()).hexdigest()))
        self.db.commit()

    def check(self, username, password):
        self.sql.execute("SELECT * FROM logins WHERE username = ? AND password = ?",
                         (username, md5(password.encode()).hexdigest()))
        data = self.sql.fetchall()
        if len(data) < 1:
            return False
        elif len(data) == 1:
            return True
        else:
            print("Duplicate login entry in database, please remove the duplicate user")

db = Login()



def login():
    username = input("Username: ")
    password = input("Password: ")

    if not db.check(username, password):
        return False
    else:
        return username

def createnew():
    username = input("New Username: ")
    while True:
        password = input("New Password: ")
        retype = input("Retype Password: ")
        if password == retype:
            break
        print("Passwords did not match!")
    db.new_user(username, password)



print('''
------------------------------
1) Login
2) Create New User
------------------------------
''')
while True:
    option = input(">> ")
    if option == "1" or option.lower == "login":
        user = login()
        if user:
            print("Welcome", user)
        else:
            print("Invalid username/password!")
            continue
        break
    elif option == "2" or option.lower == "create new user":
        createnew()
    else:
        print("Please enter one of the above options")
        continue