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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 convexhull(data, col, fill=True, point_size=4):
 """ Convex hull for a set of points :param data: points :param col: color :param fill: whether to fill the convexhull polygon or not :param point_size: size of the points on the convexhull. Points are not rendered if None """

    from geoplotlib.layers import ConvexHullLayer
    _global_config.layers.append(ConvexHullLayer(data, col, fill, point_size))