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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 hull(self):
 """ Bounding polygon as a convex hull. """

        from scipy.spatial import ConvexHull
        if len(self.coordinates) >= 4:
            inds = ConvexHull(self.coordinates).vertices
            return self.coordinates[inds]
        else:
            return self.coordinates