'Process one line from the text format answer, authority, or
additional data sections.'

def _rr_line(self, section):

    deleting = None
    token = self.tok.get(want_leading=True)
    if (not token.is_whitespace()):
        self.last_name = dns.name.from_text(token.value, None)
    name = self.last_name
    token = self.tok.get()
    if (not token.is_identifier()):
        raise dns.exception.SyntaxError
    try:
        ttl = int(token.value, 0)
        token = self.tok.get()
        if (not token.is_identifier()):
            raise dns.exception.SyntaxError
    except dns.exception.SyntaxError:
        raise dns.exception.SyntaxError
    except:
        ttl = 0
    try:
        rdclass = dns.rdataclass.from_text(token.value)
        token = self.tok.get()
        if (not token.is_identifier()):
            raise dns.exception.SyntaxError
        if ((rdclass == dns.rdataclass.ANY) or (rdclass == dns.rdataclass.NONE)):
            deleting = rdclass
            rdclass = self.zone_rdclass
    except dns.exception.SyntaxError:
        raise dns.exception.SyntaxError
    except:
        rdclass = dns.rdataclass.IN
    rdtype = dns.rdatatype.from_text(token.value)
    token = self.tok.get()
    if (not token.is_eol_or_eof()):
        self.tok.unget(token)
        rd = dns.rdata.from_text(rdclass, rdtype, self.tok, None)
        covers = rd.covers()
    else:
        rd = None
        covers = dns.rdatatype.NONE
    rrset = self.message.find_rrset(section, name, rdclass, rdtype, covers, deleting, True, self.updating)
    if (not (rd is None)):
        rrset.add(rd, ttl)
