Change this line
multi.connect("not_touched", self, "multi_is_untouched(multi)")
To
multi.connect("not_touched", self, "multi_is_untouched")
Where in your script multi
emits the not_touched
signal, use:
emit_signal("not_touched", self)
And when the not_touched
signal is defined, replace it with
signal not_touched(multi)
When you connect the signal to the function, it will automatically pass the required parameters.