def get_delta_frame_id(span0, span1):
    """Computes the minimum distance between two non-overlapping spans.
    
    Args:
         span0 (Span): First span.
         span1 (Span): Second span.
    """
    if span0.overlaps(span1):
        assert False, (span0, span1)
        return 0
    
    if span0.end < span1.start:
        return span1.start - span0.end
    else:
        return span0.start - span1.end