app.py

from flask import Flask
from blog.models import Post # ERROR.
from flask.ext.mongoengine import MongoEngine
app = Flask(__name__)
app.config["MONGODB_SETTINGS"] = {'DB': "FlaskBlog"}

db = MongoEngine(app)

models.py

import datetime
from blog.app import db


class Post(db.Document):
  title = db.StringField(max_length=100,required=True)
  content = db.StringField(max_length=1000, required=True)
  pub_date = db.DateTimeField(default=datetime.datetime.now, required=True)
  slug = db.StringField(max_length=100,required=True)

  meta = {
    'ordering': ['-pub_date']
  }