def __init__(self, preference=0, name=b'', ttl=None, **kwargs):
        """
        @param name: See L{Record_MX.name}.
        @type name: L{bytes} or L{unicode}
        """
        self.preference = int(preference)
        self.name = Name(kwargs.get('exchange', name))
        self.ttl = str2time(ttl)

        @param name: See L{Record_MX.name}.
        @type name: L{bytes} or L{unicode}
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/names/dns.py