two ESP8266 to communicate with udp using WiFiESP.h - arduino

Question

guys, i'd like to use esp8266 module and wifiesp.h. I wanna make two esp8266 modules to communicate through udp protocol. To use it, i found udp communication example. But I wonder if the example consist receive codes and send codes. Can you help me to find receive code and send code??
Is there any other send and receive code for UDP protocol??
#include <WiFiEsp.h>
#include <WiFiEspUdp.h>
// Emulate Serial1 on pins 6/7 if not present
#ifndef HAVE_HWSERIAL1
#include "SoftwareSerial.h"
SoftwareSerial Serial1(6, 7); // RX, TX
#endif
char ssid[] = "Twim"; // your network SSID (name)
char pass[] = "12345678"; // your network password
int status = WL_IDLE_STATUS; // the Wifi radio's status
unsigned int localPort = 10002; // local port to listen on
char packetBuffer[255]; // buffer to hold incoming packet
char ReplyBuffer[] = "ACK"; // a string to send back
WiFiEspUDP Udp;
void setup() {
// initialize serial for debugging
Serial.begin(115200);
// initialize serial for ESP module
Serial1.begin(9600);
// initialize ESP module
WiFi.init(&Serial1);
// check for the presence of the shield:
if (WiFi.status() == WL_NO_SHIELD) {
Serial.println("WiFi shield not present");
// don't continue:
while (true);
}
// attempt to connect to WiFi network
while ( status != WL_CONNECTED) {
Serial.print("Attempting to connect to WPA SSID: ");
Serial.println(ssid);
// Connect to WPA/WPA2 network
status = WiFi.begin(ssid, pass);
}
Serial.println("Connected to wifi");
printWifiStatus();
Serial.println("\nStarting connection to server...");
// if you get a connection, report back via serial:
Udp.begin(localPort);
Serial.print("Listening on port ");
Serial.println(localPort);
}
void loop() {
// if there's data available, read a packet
int packetSize = Udp.parsePacket();
if (packetSize) {
Serial.print("Received packet of size ");
Serial.println(packetSize);
Serial.print("From ");
IPAddress remoteIp = Udp.remoteIP();
Serial.print(remoteIp);
Serial.print(", port ");
Serial.println(Udp.remotePort());
// read the packet into packetBufffer
int len = Udp.read(packetBuffer, 255);
if (len > 0) {
packetBuffer[len] = 0;
}
Serial.println("Contents:");
Serial.println(packetBuffer);
// send a reply, to the IP address and port that sent us the packet we received
Udp.beginPacket(Udp.remoteIP(), Udp.remotePort());
Udp.write(ReplyBuffer);
Udp.endPacket();
}
}
void printWifiStatus() {
// print the SSID of the network you're attached to:
Serial.print("SSID: ");
Serial.println(WiFi.SSID());
// print your WiFi shield's IP address:
IPAddress ip = WiFi.localIP();
Serial.print("IP Address: ");
Serial.println(ip);
// print the received signal strength:
long rssi = WiFi.RSSI();
Serial.print("signal strength (RSSI):");
Serial.print(rssi);
Serial.println(" dBm");
}