'list' object is not callable with Zope python script

Hello ZMS users,

I'm experiencing a strange problem with a python script used in a ZMS  
shop object.
I've got a python script with the id "shop_current" with the following  
content:

## Script (Python) "shop_current"
##bind container=container
##bind context=context
##bind namespace=
##bind script=script
##bind subpath=traverse_subpath
##parameters=id=None,vat=True
##title=
##
# --// BO shop_current(id=None,vat=True) //--

from Products.PythonScripts.standard import html_quote
request = container.REQUEST
RESPONSE =  request.RESPONSE
session = context.REQUEST.SESSION

quantities=session.get('items', {})
items=[]

for id, quantity in quantities.items():
	
	if ( vat == False ):
		item = context.shop_getitems(id=id, vat=False)
	else:
		item = context.shop_getitems(id=id, vat=True)

	if item is not None:
		item['quantity']=quantity
		items.append(item)

return items

# --// EO shop_current //--

and when I call it from a DTML template with <dtml-let  
so="shop_callable(vat=False)"><dtml-in so>....</dtml-in></dtml-let> I  
get the error:

Error Type: TypeError
Error Value: 'list' object is not callable

When I don't pass vat and use <dtml-let "shop_callable"> it works but  
of course the parameter is not passed to the script.

BUT:
When I create another Script (Python) from inside the ZMI (not ZMS  
interface) and put the same code in there it work's fine.

Any idea why this doesn't work with script created from the ZMS  
content object configuration?

Mit freundlichen Grüßen
Sebastian Tänzer

[tm] tänzermedien e.K.
Agentur für Online-Medien

Kekuléstr. 39
53115 Bonn

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