      # so we check in addition that the end is larger than the start of the range.
        # NOTE: if the given range has zero length, then any annotation that starts before or at start
        # AND ends at or after start==end is overlapping
        if start == end:
            # in order to check what is overlapping with the zero length span, we need to find
            # intervals which start before the start of that span AND end at least one after that span;
            # or intervals which start at th