How to use the bigcommerce.api.BigcommerceApi function in bigcommerce

        self.assertRaises(Exception, lambda: bigcommerce.api.BigcommerceApi(client_id='123', basic_auth=('admin', 'token')))

def auth_callback():
    # Put together params for token request
    code = flask.request.args['code']
    context = flask.request.args['context']
    scope = flask.request.args['scope']
    store_hash = context.split('/')[1]
    redirect = app.config['APP_URL'] + flask.url_for('auth_callback')

    # Fetch a permanent oauth token. This will throw an exception on error,
    # which will get caught by our error handler above.
    client = BigcommerceApi(client_id=client_id(), store_hash=store_hash)
    token = client.oauth_fetch_token(client_secret(), code, context, scope, redirect)
    bc_user_id = token['user']['id']
    email = token['user']['email']
    access_token = token['access_token']

    # Create or update store
    store = Store.query.filter_by(store_hash=store_hash).first()
    if store is None:
        store = Store(store_hash, access_token, scope)
        db.session.add(store)
        db.session.commit()
    else:
        store.access_token = access_token
        store.scope = scope
        db.session.add(store)
        db.session.commit()

def index():
    # Lookup user
    storeuser = StoreUser.query.filter_by(id=flask.session['storeuserid']).first()
    if storeuser is None:
        return "Not logged in!", 401
    store = storeuser.store
    user = storeuser.user

    # Construct api client
    client = BigcommerceApi(client_id=client_id(),
                            store_hash=store.store_hash,
                            access_token=store.access_token)

    # Fetch a few products
    products = client.Products.all(limit=10)

    # Render page
    context = dict()
    context['products'] = products
    context['user'] = user
    context['store'] = store
    context['client_id'] = client_id()
    context['api_url'] = client.connection.host
    return render('index.html', context)

def load():
    # Decode and verify payload
    payload = flask.request.args['signed_payload']
    user_data = BigcommerceApi.oauth_verify_payload(payload, client_secret())
    if user_data is False:
        return "Payload verification failed!", 401

    bc_user_id = user_data['user']['id']
    email = user_data['user']['email']
    store_hash = user_data['store_hash']

    # Lookup store
    store = Store.query.filter_by(store_hash=store_hash).first()
    if store is None:
        return "Store not found!", 401

    # Lookup user and create if doesn't exist (this can happen if you enable multi-user
    # when registering your app)
    user = User.query.filter_by(bc_id=bc_user_id).first()
    if user is None: