Getting builtins.TypeError TypeError: __init__() takes from 1 to 2 positional arguments but 3 were given

from flask import (Flask, g, render_template, flash, redirect, url_for)
from flask.ext.bcrypt import check_password_hash
from flask.ext.login import (LoginManager, login_user, logout_user, 
                            login_required, current_user)

import forms
import models

DEBUG = True
PORT = 8000
HOST = '0.0.0.0'

app = Flask(__name__)
app.secret_key = 'asdnafnj#46sjsnvd(*$43sfjkndkjvnskb6441531@#$$6sddf'
"""here secret_key is a random string of alphanumerics"""

login_manager = LoginManager()
login_manager.init_app(app)
login_manager.login_view = 'login'

@login_manager.user_loader
def load_user(userid):
    try:
        return models.User.get(models.User.id == userid)
    except models.DoesNotExist:
        return None


@app.before_request
def before_request():
    """Connect to database before each request
        g is a global object, passed around all time in flask, used to setup things which 
        we wanna have available everywhere.
    """
    g.db = models.DATABASE
    g.db.connect()
    g.user = current_user


@app.after_request
def after_request(response):
    """close all database connection after each request"""
    g.db.close()
    return response


@app.route('/register', methods = ('GET','POST'))
def register():
    form = forms.RegisterForm()
    if form.validate_on_submit():
        flash("Congrats, Registered Successfully!", "success")
        models.User.create_user(
            username = form.username.data,
            email = form.email.data,
            password = form.password.data
        )
        return redirect(url_for('index'))
    return render_template('register.html', form = form)


@app.route('/login', methods = ('GET', 'POST'))
def login():
    form = forms.LoginForm()
    if form.validate_on_submit():
        try:
            user = models.User.get(models.User.email == form.email.data)
        except models.DoesNotExist:
            flash("Your email or password does not match", "error")
        else:
            if check_password_hash(user.password, form.password.data):
                login_user(user) 
                """Creating a session on user's browser"""
                flash("You have been logged in", "success")
                return redirect(url_for('index'))
            else:
                flash("Your email or password does not match", "error")
    return render_template('login.html', form = form)

@app.route('/logout')
@login_required
def logout():
    logout_user()
    flash("You have been logged out.")
    return redirect(url_for('login'))


@app.route('/new_post', methods = ('GET', 'POST'))
@login_required
def post():
    form = forms.PostForm()
    if form.validate_on_submit():
        models.Post.create(user = g.user.id, 
                            content = form.content.data.strip())
        flash("Message Posted: Thanks!", "success")
        return redirect(url_for('index'))
    return render_template('post.html', form = form)



@app.route('/')
def index():
    stream = models.Post.select().limit(100)
    return render_template('stream.html', stream = stream)

@app.route('/stream')
@app.route('/stream/<username>')
def stream(username = None):
    template = 'stream.html'
    if username and username != current_user.username:
        user = models.User.select().where(models.User.username**username).get()
        stream = user.posts.limit(100)
    else:
        stream = current_user.get_stream().limit(100)
        user = current_user
    if username:
        template = 'user_stream.html'
    return render_template(template, stream = stream, user = user)



if __name__ == '__main__':
    models.initialize()
    try:
        models.User.create_user(
            username = 'niteshsharma',
            email = 'nbsharma@outlook.com',
            password = 'password',
            admin = True
        )
    except ValueError:
        pass
    app.run(debug=DEBUG,host = HOST, port = PORT)