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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 load_features_and_arrays(prefix, mmap_mode='r'):
 """ Returns the features and NumPy arrays that were saved with save_features_and_arrays. Parameters prefix : str Path to where data are saved mmap_mode : {None, 'r+', 'r', 'w+', 'c'} Mode in which to memory-map the file. See np.load for details. """

    features = pybedtools.BedTool(prefix + '.features')
    arrays = np.load(prefix + '.npz', mmap_mode=mmap_mode)
    return features, arrays