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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 set_features(self, partition=1):
 """ Parses market data JSON for technical analysis indicators Args: partition: Int of how many dates to take into consideration when evaluating technical analysis indicators. Returns: Pandas DataFrame instance with columns as numpy.float32 features. """

        if len(self.json) < partition + 1:
            raise ValueError('Not enough dates for the specified partition size: {0}.  Try a smaller partition.'.format(partition))

        data = []
        for offset in range(len(self.json) - partition):
            json = self.json[offset : offset + partition]
            data.append(eval_features(json))
        return pd.DataFrame(data=data, dtype=np.float32)