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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 _parse_mut(mut):
 """ Parse mutation field to get position and nts. """

    multiplier = 1
    if mut.startswith("-"):
        mut = mut[1:]
        multiplier = -1
    nt = mut.strip('0123456789')
    pos = int(mut[:-2]) * multiplier
    return nt, pos