title: Flask DateTime won't set with default datetime.utcnow
body: <p>I am new to SQLAlchemy and have been unable to set the DateTime for created.  I have tried using the "default" option found in many examples.  I have also tried setting it manually (I have it commented out).  Neither have worked so far.  Any help would be appreciated.</p>
  
  <pre><code>models.py
  
  import datetime
  from flask.ext.sqlalchemy import SQLAlchemy
  from werkzeug import generate_password_hash, check_password_hash
  
  db = SQLAlchemy()
  
  class User(db.Model):
  
    __tablename__    = 'users'
    uid              = db.Column(db.Integer, primary_key=True)
    firstname        = db.Column(db.String(40))
    lastname         = db.Column(db.String(40))
    email            = db.Column(db.String(120), unique=True)
    created          = db.Column(db.DateTime, default=datetime.datetime.utcnow())
    confirmed        = db.Column(db.DateTime, nullable=True)
    pwdhash          = db.Column(db.String(100))
  
    def __init__(self, firstname, lastname, email, password):
      self.firstname = firstname.title()
      self.lastname  = lastname.title()
      self.email     = email.lower()
      self.set_password(password)
      #self.created   = datetime.datetime.utcnow()
      self.confirmed = None
  
    def set_password(self, password):
      self.pwdhash   = generate_password_hash(password)
  
    def check_password(self, password):
      return check_password_hash(self.pwdhash, password)
  
  routes.py
  
  from tasks import app
  from datetime import datetime
  from flask import render_template, request, flash, session, url_for, redirect
  from forms import ContactForm, SignupForm, SigninForm
  from flask.ext.mail import Message, Mail
  from models import db, User, Tags, Tasks
  
  @app.route('/signup', methods=['GET', 'POST'])
  def signup():
    form = SignupForm()
  
    if 'email' in session:
      return redirect(url_for('profile')) 
  
    if request.method == 'POST':
      if form.validate() == False:
        return render_template('signup.html', form=form)
      else:
        newuser = User(form.firstname.data, form.lastname.data, form.email.data, form.password.data)
        db.session.add(newuser)
        db.session.commit()
  
        session['email'] = newuser.email
        return redirect(url_for('profile'))
  
    elif request.method == 'GET':
      return render_template('signup.html', form=form)
  </code></pre>