[Zope] calling dtmlMethod from python

Can anyone please help with this, I'm new to zope and trying to write a simple python script to handle some logic which will then call a dtml method. I'm calling the method as such: context.scReport() The error I'm getting back is Error Type: KeyError Error Value: standard_html_header standard_html_header is being called from the scReport method which suggests the scReport method is being invoked but why are we getting an error?? Any suggestions, TIA Shaneo