s. So
        Span(1,1) overlaps with Span(1,1) because the integer 1 is in both number sets. Span(1,1) overlaps
        with Span(1,2) but not with Span(2,2) or Span(2,3).   Span(1,1) also does not overlap with Span(0,1).


        Args:
            start: the start offset of the span
            end: the end offset of the span, the offset of the first character after the span that does not
                belong to the span
        &#34;&#34;&#34;
        assert start is not None
        assert end is not