Using version 3.35.1 <u>out of the box</u> (i.e. neither loading any extension nor defining any functions), consider this session: ``` SQLite version 3.35.1 2021-03-15 16:53:57 Enter ".help" for usage hints. sqlite> select count(*) from pragma_function_list where builtin != 1; count(*) -------- 84 sqlite> select * from pragma_function_list where name like 'geo%'; name builtin type enc narg flags ---------------------- ------- ---- ---- ---- ------- geopoly_regular 0 s utf8 4 2099200 geopoly_contains_point 0 s utf8 3 2099200 geopoly_debug 0 s utf8 1 524288 geopoly_bbox 0 s utf8 1 2099200 geopoly_overlap 0 s utf8 2 2099200 geopoly_xform 0 s utf8 7 2099200 geopoly_svg 0 s utf8 -1 2099200 geopoly_area 0 s utf8 1 2099200 geopoly_blob 0 s utf8 1 2099200 geopoly_within 0 s utf8 2 2099200 geopoly_json 0 s utf8 1 2099200 geopoly_ccw 0 s utf8 1 2099200 geopoly_group_bbox 0 a utf8 1 2099200 sqlite> ``` So, the geo* functions are <b>NOT</b> <i>written and maintained by the authors of SQLite3</i> (as you so succinctly described) and I did not add/define them. 1. Where do they come from? 2. Can they be used outright? 3. Can they be used subject to some other configuration oe pre-condition?