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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 collect(self):
 """ Collect and publish netfilter counters """

        cmd = [self.config['bin'], "list"]

        if str_to_bool(self.config['reset']):
            cmd.append("reset")

        if str_to_bool(self.config['use_sudo']):
            cmd.insert(0, self.config['sudo_cmd'])

        # We avoid use of the XML format to mtaintain compatbility with older
        # versions of nfacct and also to avoid the bug where pkts and bytes were
        # flipped

        # Each line is of the format:
        # { pkts = 00000000000001121700, bytes = 00000000000587037355 } = ipv4;
        matcher = re.compile("{ pkts = (.*), bytes = (.*) } = (.*);")
        lines = Popen(cmd, stdout=PIPE).communicate()[0].strip().splitlines()

        for line in lines:
            matches = re.match(matcher, line)
            if matches:
                num_packets = int(matches.group(1))
                num_bytes = int(matches.group(2))
                name = matches.group(3)
                self.publish(name + ".pkts", num_packets)
                self.publish(name + ".bytes", num_bytes)