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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 zip_namedtuple(nt_list):
 """ accept list of namedtuple, return a dict of zipped fields """

    if not nt_list:
        return dict()
    if not isinstance(nt_list, list):
        nt_list = [nt_list]
    for nt in nt_list:
        assert type(nt) == type(nt_list[0])
    ret = {k : [v] for k, v in nt_list[0]._asdict().items()}
    for nt in nt_list[1:]:
        for k, v in nt._asdict().items():
            ret[k].append(v)
    return ret