def fofn_to_fns(fn):
    """Return a list of file names of files in input fofn filehandler.
    ...doctest:
        >>> fn = op.join(op.dirname(op.dirname(op.dirname(__file__))), 'tests', 'data', 'bams.fofn')
        >>> fofn_to_fns(fn)
        ['align_p.bam', 'align_m.bam', 'align_f.bam']
    """
    return [f.strip() for f in open(fn, 'r') if len(f.strip()) != 0 and not f.startswith('#')]