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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 arp_packet(opcode, src_mac, src_ip, dst_mac, dst_ip):
 """ Generate ARP packet with ethernet encapsulated. """

        # Generate ethernet header first.
        pkt = packet.Packet()
        eth_pkt = ethernet.ethernet(dst_mac, src_mac, ETH_TYPE_ARP)
        pkt.add_protocol(eth_pkt)

        # Use IPv4 ARP wrapper from packet library directly.
        arp_pkt = arp.arp_ip(opcode, src_mac, src_ip, dst_mac, dst_ip)
        pkt.add_protocol(arp_pkt)

        pkt.serialize()
        return pkt.data