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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 get_json(self):
 """ Gets market chart data from today to a previous date """

        today = dt.now()
        DIRECTION = 'last'
        epochs = date.get_end_start_epochs(today.year, today.month, today.day,
                                           DIRECTION, self.unit, self.count)
        return poloniex.chart_json(epochs['shifted'], epochs['initial'],
                                   self.period, self.symbol)[0]