Add missing import and remove unconditional exception causing Mock mode by default

grocery_transactions.py

@@ -12,6 +12,7 @@ from widgets import (
     NoTabCheckBox,
     AutoCompleteEdit,
     AutoCompleteFloatEdit,
+    _set_focus_path,
 )
 import sys
 import urwid
@@ -31,7 +32,7 @@ except:
     password = ''
 
 try:
-    raise Exception
+    import psycopg2
     from psycopg2.sql import SQL
     from db_utils import cursor_as_dict
     import os