generate_password_hash：对密码明文密码加盐，生成加密后的hash字符串
generate_password_hash('123') 'pbkdf2:sha256:150000$DWt7OJXb$1e561fab7cf24bd0bd691c8b3bd7d235867cb3b567043b80a46ee367b8814467'
check_password_hash：将密码和hash字符串进行比对，返回true或false
check_password_hash(generate_password_hash('123'),'123') True