In python, how to set the show 'Movie Import settings' flag?

Using Python, I would like to add the Movie import settings to the VSE Workspace filebrowser if the Movie filter is selected. When using the Add Menu some settings are changed i C which makes the filebrowser show the settings.

The C code(which I know nothing about) which does the trick, is here:
(search for SEQUENCER_OT_movie_strip_add)
developer.blender.org/diffusion/B/browse/master/source/blender/editors/space_sequencer/sequencer_add.c

void SEQUENCER_OT_movie_strip_add(struct wmOperatorType ot)
3e6a1bc60b56 {
44505b38df55
e12c08e8d170 /
identifiers /
ot->name = “Add Movie Strip”;
ot->idname = “SEQUENCER_OT_movie_strip_add”;
ot->description = “Add a movie strip to the sequencer”;
/
api callbacks */
ot->invoke = sequencer_add_movie_strip_invoke;
ot->exec = sequencer_add_movie_strip_exec;
ot->cancel = sequencer_add_cancel;
ot->ui = sequencer_add_draw;

ot->poll = ED_operator_sequencer_active_editable;

/* flags */
ot->flag = OPTYPE_REGISTER OPTYPE_UNDO;

WM_operator_properties_filesel(ot,
FILE_TYPE_FOLDER FILE_TYPE_MOVIE,
FILE_SPECIAL,
FILE_OPENFILE,
WM_FILESEL_FILEPATH WM_FILESEL_RELPATH WM_FILESEL_FILES,
FILE_DEFAULTDISPLAY,
FILE_SORT_ALPHA);
sequencer_generic_props__internal(ot, SEQPROP_STARTFRAME);
RNA_def_boolean(ot->srna, “sound”, true, “Sound”, “Load sound with the movie”);
RNA_def_boolean(ot->srna,
“use_framerate”,
true,
“Use Movie Framerate”,
“Use framerate from the movie to keep sound and video in sync”);
3e6a1bc60b56 }

My question is: How can I, in python, call/set the flag to make the workspace filebrowser show the import settings?

An illustration:

A more detailed description of what i need it for:
https://developer.blender.org/T65746