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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 _build_graph(self):
        '''Build Rickshaw graph syntax with all data'''

        # Set palette colors if necessary
        if not self.colors:
            self.palette = self.env.get_template('palette.js')
            self.template_vars.update({'palette': self.palette.render()})
            self.colors = {x['name']: 'palette.color()' for x in self.json_data}

        template_vars = []
        for index, dataset in enumerate(self.json_data):
            group = 'datagroup' + str(index)
            template_vars.append({'name': str(dataset['name']),
                                  'color': self.colors[dataset['name']],
                                  'data': 'json[{0}].data'.format(index)})

        variables = {'dataset': template_vars, 'width': self.width,
                     'height': self.height, 'render': self.renderer,
                     'chart_id': self.chart_id}
        if not self.y_zero:
            variables.update({'min': "min: 'auto',"})

        graph = self.env.get_template('graph.js')
        self.template_vars.update({'graph': graph.render(variables)})