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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_image_dimension(bbox, width=None, height=None):
 """ Given bounding box and one of the parameters width or height it will return the other parameter that will best fit the bounding box dimensions :param bbox: bounding box :type bbox: geometry.BBox :param width: image width or None if height is unknown :type width: int or None :param height: image height or None if height is unknown :type height: int or None :return: width or height rounded to integer :rtype: int """

    utm_bbox = to_utm_bbox(bbox)
    east1, north1 = utm_bbox.lower_left
    east2, north2 = utm_bbox.upper_right
    if isinstance(width, int):
        return round(width * abs(north2 - north1) / abs(east2 - east1))
    return round(height * abs(east2 - east1) / abs(north2 - north1))