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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 add_new_host(self, hostname, ipv4addr, comment=None):
 """Add or update a host in the infoblox, overwriting any IP address entries. :param str hostname: Hostname to add/set :param str ipv4addr: IP Address to add/set :param str comment: The comment for the record """

        host = Host(self.session, name=hostname)
        if host.ipv4addrs:
            host.ipv4addrs = []
        host.add_ipv4addr(ipv4addr)
        host.comment = comment
        return host.save()