405 Method Not Allowed - Post User

import json
from flask import jsonify, Blueprint, abort, make_response

from flask_restful import (Resource, Api, reqparse,
                           inputs, fields, marshal,
                           marshal_with, url_for)

import models

user_fields = {
    'username': fields.String,
}


class UserList(Resource):
    def __init__(self):
        self.reqparse = reqparse.RequestParser()
        self.reqparse.add_argument(
            'username',
            required=True,
            help='No username provided',
            location=['form', 'json']
        )
        self.reqparse.add_argument(
            'email',
            required=True,
            help='No email provided',
            location=['form', 'json']
        )
        self.reqparse.add_argument(
            'password',
            required=True,
            help='No password provided',
            location=['form', 'json']
        )
        self.reqparse.add_argument(
            'verify_password',
            required=True,
            help='No password verification provided',
            location=['form', 'json']
        )
        super().__init__()

        def post(self):
            args = self.reqparse.parse_args()
            if args['password'] == args['verify_password']:
                user = models.User.create_user(**args)
                return marshal(user, user_fields), 201
            return make_response(
                json.dumps({
                    'error': 'Password and password verification do not match'
                }), 400)


users_api = Blueprint('resources.users', __name__)
api = Api(users_api)
api.add_resource(
    UserList,
    '/users',
    endpoint='users'
)