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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 _compute_quads(self, element, data, mapping):
 """ Computes the node quad glyph data.x """

        quad_mapping = {'left': 'x0', 'right': 'x1', 'bottom': 'y0', 'top': 'y1'}
        quad_data = dict(data['scatter_1'])
        quad_data.update({'x0': [], 'x1': [], 'y0': [], 'y1': []})
        for node in element._sankey['nodes']:
            quad_data['x0'].append(node['x0'])
            quad_data['y0'].append(node['y0'])
            quad_data['x1'].append(node['x1'])
            quad_data['y1'].append(node['y1'])
            data['scatter_1'].update(quad_data)
        data['quad_1'] = data['scatter_1']
        mapping['quad_1'] = quad_mapping