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Python Build a Social Network with Flask Making Strong Users What's a method like you doing in a class like this?

Khoa Nguyen
Khoa Nguyen
1,781 Points
Posted by Khoa Nguyen
Khoa Nguyen
1,781 Points

What is purpose of class Meta ? and Why is my code wrong

Hello,

Can you explain what is class Meta and Why my code is wrong

models.py 
import datetime

from flask.ext.bcrypt import generate_password_hash
from flask.ext.login import UserMixin
from peewee import *

database = SqliteDatabase(':memory:')

class User(Model):
    email = CharField(unique=True)
    password = CharField(max_length=100)
    join_date = DateTimeField(default=datetime.datetime.now)
    bio = CharField(default='')

    class Meta:
        database = database
    @classmethod
    def new(cls, email, password):
      cls.create(email, generate_password_hash(password))

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,454 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,454 Points

When Python creates a class object, special construction instructions can be provided. This is done through the Meta class. In this case, the Model base class includes methods for creating and saving instances of this class to a database. This requires knowing which database to use. Since the database isn't part of the class itself, this class constructor information is provided through the special Meta class.

For a great read on the details of using class Meta in Python, see this StackOverflow answer Classes as Objects

Your code fails because .create() is looking for keyword argument, not positional argument:

    @classmethod
    def new(cls, email, password):
        cls.create(email=email, password=generate_password_hash(password))