Bug #1975595 “regex search and template search problems” : Bugs : calibre

I am trying to search for book titles that end with text within parenthesis e.g. My title (subtitle)

while at the same time excluding those that contain numbers inside the parenthesis e.g. My title (3)

I tried using the following regex search

title:~[^\d]\)$

It does not return any error, but also does not return the results I expect (it return no books at all). To remedy this I resorted to template search as below

template:”program:
 if ‘[^\d]\)$’ in $title then ‘true’ else ‘false’ fi#@#:t:true”

This gives me the error below:

Interpreter: Error during string comparison: operator ‘in’ – line number 2

The template does not give the same error in template dialog, only when used in search.

I am using calibre 5.99.9