Flask Error: typeerror run () received an unexpected keyword argument to 'host'

I created a virtual boxing website with Flask. The website can be opened on the local host, but I cannot open it through port forwarding, so I changed the code from manage.run()to manage.run(host='0.0.0.0').

The problem is that I get this error:

typeerror run() got an unexpected keyword argument 'host'. 

A similar error occurs when changing manage.run()to manage.run(debug=True). I just followed the Flask documentation. http://flask.pocoo.org/docs/quickstart/#a-minimal-application Can someone tell me why I am getting this error?

#!/usr/bin/env python
#-*- coding:utf-8 -*-

"""Manage Script."""

from sys import stderr, exit

from flask.ext.script import Manager, prompt_bool

from szupa import create_app
from szupa.extensions import db
from szupa.account.models import User
from szupa.context import create_category_db


app = create_app()
manager = Manager(app)


@manager.command
def initdb():
    """Initialize database."""
    db.create_all()
    create_category_db()


@manager.command
def migrate(created, action="up"):
    module_name = "migrates.migrate%s" % created
    try:
        module = __import__(module_name, fromlist=["migrates"])
    except ImportError:
        print >> stderr, "The migrate script '%s' is not found." % module_name
        exit(-1)
    if prompt_bool("Confirm to execute migrate script '%s'" % module_name):
        try:
            action = getattr(module, action)
        except AttributeError:
            print >> stderr, "The given action '%s' is invalid." % action
            exit(-1)
        action(db)
        print >> stderr, "Finished."


@manager.command
def dropdb():
    """Drop database."""
    if prompt_bool("Confirm to drop all table from database"):
        db.drop_all()


@manager.command
def setadmin(email):
    """Promote a user to administrator."""
    user = User.query.filter_by(email=email).first()
    if not user:
        print >> stderr, "The user with email '%s' could not be found." % email
        exit(-1)
    else:
        user.is_admin = True
        db.session.commit()


if __name__ == "__main__":
    manager.run()