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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_json(fn_json):
 """read json information"""

    is_json = set()
    is_db = {}
    with open(fn_json) as handle:
        data = json.load(handle)
        # original Py 2.y core
        #for item in data[0].values():
        #    seqs_name = map(lambda (x): x.keys(), item['seqs'])
        # rewrite by 2to3
        for item in list(data[0].values()):
            seqs_name = [list(x.keys()) for x in item['seqs']]
            db_name = item['valid'] if "valid" in item else None
            [is_json.add(name[0]) for name in seqs_name]
            if db_name:
                [is_db.update({name[0]: ",".join(db_name)}) for name in seqs_name]
    return is_json, is_db