def bounds_span(bound1, bound2):
    """Produces the span of two 1D bounds, represented as tuples.
    
    Args:
        bound1, bound2: Bounds to merge. They are in the form of pair
        (start, end).
    
    Returns:
        The span of the bounds bound.
    """
    return (min(bound1[0], bound2[0]),max(bound1[1], bound2[1]))