Fatal error: Call to undefined function wpsc_cart_item_count()

Hi,
I have got this error when install woocommerce plugin with Balita theme

( ! ) Fatal error: Call to undefined function wpsc_cart_item_count() in C:\wamp64\www\thanhshop\wp-content\themes\balita\header.php on line 78
Call Stack
#	Time	Memory	Function	Location
1	0.0004	240408	{main}( )	...\index.php:0
2	0.0007	243512	require( 'C:\wamp64\www\thanhshop\wp-blog-header.php' )	...\index.php:17
3	0.7464	36850440	require_once( 'C:\wamp64\www\thanhshop\wp-includes\template-loader.php' )	...\wp-blog-header.php:16
4	0.7534	37021624	include( 'C:\wamp64\www\thanhshop\wp-content\plugins\woocommerce\templates\archive-product.php' )	...\template-loader.php:89
5	0.7534	37021760	get_header( )	...\archive-product.php:22
6	0.7535	37023320	locate_template( )	...\general-template.php:45
7	0.7539	37023568	load_template( )	...\template.php:521
8	0.7545	37074944	require_once( 'C:\wamp64\www\thanhshop\wp-content\themes\balita\header.php' )

I have installed wordpress woocommerce with Balita theme and get this error.
As i researcher some fix workaround and install wp-e-commerce plugin can be fixed this issue. But it also raise another issue when add new products, category,… because wp-e-commerce create another instance of woocommerce and doesn’t support for localization as woocommerce before.
Does the woocomerce update api and now it requires to update to wp-e-commerce? any solution to use the woocommerce standalone as before?

Thanks,
Lam

https://www.ads-software.com/plugins/woocommerce/