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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 update_bounds(self, bounds):
        '''Update cylinders start and end positions

        '''
        starts =  bounds[:,0,:]
        ends = bounds[:,1,:]

        self.bounds = bounds
        self.lengths =  np.sqrt(((ends - starts)**2).sum(axis=1))
        
        vertices, normals, colors = self._process_reference()
        
        self.tr.update_vertices(vertices)
        self.tr.update_normals(normals)