'Function to delete the cached arp entries.'

def _delete_arp_cache_for_internal_port(self, subnet_id):

    arp_delete = set()
    for arp_entry in self._pending_arp_set:
        if (subnet_id == arp_entry.subnet_id):
            arp_delete.add(arp_entry)
    self._pending_arp_set -= arp_delete
