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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 write_otu_file(otu_ids, fp):
 """ Write out a file containing only the list of OTU IDs from the kraken data. One line per ID. :type otu_ids: list or iterable :param otu_ids: The OTU identifiers that will be written to file. :type fp: str :param fp: The path to the output file. """

    fpdir = osp.split(fp)[0]

    if not fpdir == "" and not osp.isdir(fpdir):
        raise RuntimeError("Specified path does not exist: {}".format(fpdir))

    with open(fp, 'wt') as outf:
        outf.write('\n'.join(otu_ids))