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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 check_origin(self):
 """Do some simple checking of the zone's origin. @raises dns.zone.NoSOA: there is no SOA RR @raises dns.zone.NoNS: there is no NS RRset @raises KeyError: there is no origin node """

        if self.relativize:
            name = dns.name.empty
        else:
            name = self.origin
        if self.get_rdataset(name, dns.rdatatype.SOA) is None:
            raise NoSOA
        if self.get_rdataset(name, dns.rdatatype.NS) is None:
            raise NoNS