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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 from_rdata_list(name, ttl, rdatas):
 """Create an RRset with the specified name and TTL, and with the specified list of rdata objects. @rtype: dns.rrset.RRset object """


    if isinstance(name, (str, unicode)):
        name = dns.name.from_text(name, None)

    if len(rdatas) == 0:
        raise ValueError("rdata list must not be empty")
    r = None
    for rd in rdatas:
        if r is None:
            r = RRset(name, rd.rdclass, rd.rdtype)
            r.update_ttl(ttl)
            first_time = False
        r.add(rd)
    return r