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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 _read_precursor(precursor, sps):
 """ Load precursor file for that species """

    hairpin = defaultdict(str)
    name = None
    with open(precursor) as in_handle:
        for line in in_handle:
            if line.startswith(">"):
                if hairpin[name]:
                    hairpin[name] = hairpin[name] + "NNNNNNNNNNNN"
                name = line.strip().replace(">", " ").split()[0]
            else:
                hairpin[name] += line.strip()
        hairpin[name] = hairpin[name] + "NNNNNNNNNNNN"
    return hairpin