A convenient wrapper for IPv4 ARP for Ethernet.

    This is an equivalent of the following code.

        arp(ARP_HW_TYPE_ETHERNET, ether.ETH_TYPE_IP, \
               6, 4, opcode, src_mac, src_ip, dst_mac, dst_ip)

def arp_ip(opcode, src_mac, src_ip, dst_mac, dst_ip):
    """A convenient wrapper for IPv4 ARP for Ethernet.

    This is an equivalent of the following code.

        arp(ARP_HW_TYPE_ETHERNET, ether.ETH_TYPE_IP, \
               6, 4, opcode, src_mac, src_ip, dst_mac, dst_ip)
    """
    return arp(ARP_HW_TYPE_ETHERNET, ether.ETH_TYPE_IP,
               6,  # ether mac address length
               4,  # ipv4 address length,
               opcode, src_mac, src_ip, dst_mac, dst_ip)