Hi Everyone!
This is my first time posting here and I’m just getting started on my Frappe journey. 
I have attempted to set a Virtual DocField that I have coded using the Server Scripts directly from Desk as the Title field for a new DocType, but am getting the following error when I try and save the DocType:
{doc.first_name} is not a valid fieldname pattern. It should be {field_name}.
I have successfully been able to set a Virtual DocField as the Title Field when it is defined as a Python property in the DocType controller however.
Here is the setup where I get the error:
Any help or guidance is much appreciated. Thanks for your time!