Here is an other example

• Let's say my product is named MyProduct?
• I want to change the way the cart looks like because I want to add a line at the end of the cart to show if there is a discount or not.
• In the end, I want to change/override the cart-listing.pt template, so I will create a new cart-listing.py template and put it in my skins folder
• To do that, I will create an overrides.zcml file in /MyProduct?
• in this file I will put the following code:

<configure 
  xmlns="http://namespaces.zope.org/zope"
  xmlns:browser="http://namespaces.zope.org/browser">
  
  <browser:viewlet
       name="10cart-listing"
       manager="Products.PloneGetPaid.interfaces.IGetPaidCartViewletManager"
       template="skins/cart-listing.pt"
       class="Products.MyProduct.browser.WRJShoppingCartListing"
       permission="zope2.View"
       />

</configure>

• Then I need to create the view class that will override the ShoppingCartListing? view class (I chose to put it in browser.py):

from Products.PloneGetPaid.browser.cart import ShoppingCartListing
class WRJShoppingCartListing(ShoppingCartListing):
    """
    """
    template = ZopeTwoPageTemplateFile('skins/cart-listing.pt')
    
    def __init__( self, *args, **kw):
        super( WRJShoppingCartListing, self ).__init__( *args, **kw )

• You just have to restart your instance and you will be able to do the changes you want to the template.