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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_long_features(self, features, columns_to_set=[], partition=2):
 """ Sets features of double the duration Example: Setting 14 day RSIs to longer will create add a feature column of a 28 day RSIs. Args: features: Pandas DataFrame instance with columns as numpy.float32 features. columns_to_set: List of strings of feature names to make longer 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. """

        # Create long features DataFrame
        features_long = self.set_features(partition=2 * partition)

        # Remove features not specified by args.long
        unwanted_features = [f for f in features.columns if f not in columns_to_set]
        features_long = features_long.drop(unwanted_features, axis=1)

        # Prefix long columns with 'long_' to fix naming conflicts
        features_long.columns = ['long_{0}'.format(f) for f in features_long.columns]

        # Merge the two DataFrames
        skip = partition
        return pd.concat([features[skip:].reset_index(drop=True),
                         features_long],
                         axis=1)