LIST stack()
This function returns the call stack for the current task. Each element in the list is a list itself, representing a specific frame. The first element represents the first frame, and so on, up to the current frame.
Each frame list is ordered as follows:
atomic() | caller() | cancel() | definer() | method() | pause() | refresh() | resume() | sender() | stack() | suspend() | task_id() | tasks() | this() | tick() | ticks_left() | set_user() | user() | pass() | task_info() | call_trace() | debug_callers()