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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 filter_empty_files(files, ifo=None):
 """Remove empty PyCBC-HDF5 files from a list Parameters files : `list` A list of file paths to test. ifo : `str`, optional prefix for the interferometer of interest (e.g. ``'L1'``), include this for a more robust test of 'emptiness' Returns ------- nonempty : `list` the subset of the input ``files`` that are considered not empty See also -------- empty_hdf5_file for details of the 'emptiness' test """

    return type(files)([f for f in files if not empty_hdf5_file(f, ifo=ifo)])