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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 line_ribbon(self):
        '''Display the protein secondary structure as a white lines that passes through the
           backbone chain.

        '''
        # Control points are the CA (C alphas)
        backbone = np.array(self.topology['atom_names']) == 'CA'
        smoothline = self.add_representation('smoothline', {'coordinates': self.coordinates[backbone],
                                                            'color': 0xffffff})

        def update(self=self, smoothline=smoothline):
            self.update_representation(smoothline, {'coordinates': self.coordinates[backbone]})
        self.update_callbacks.append(update)

        self.autozoom(self.coordinates)