Code explanation

Hi I merged tow codes "Fingerprint" and "Servo" to control servo movement with fingerprint to open door lock I found project on DIY site but always with library missing error message so I merged these tow codes but I have problem with the servo getting in loop may some one please make notes on the code so I can understand what is going so I can modify it

#include <Adafruit_Fingerprint.h>
#include <SoftwareSerial.h>
#include <Servo.h>

Servo myservo;
int getFingerprintIDez();
int pos = 0;
// pin #2 is IN from sensor (GREEN wire)
// pin #3 is OUT from arduino  (WHITE wire)
SoftwareSerial mySerial(2, 3);


Adafruit_Fingerprint finger = Adafruit_Fingerprint(&mySerial);

void setup()  
{
  myservo.attach(9);  // attaches the servo on pin 9 to the servo object
  Serial.begin(9600);
  Serial.println("fingertest");

  // set the data rate for the sensor serial port
  finger.begin(57600);
  
  if (finger.verifyPassword()) {
    Serial.println("Found fingerprint sensor!");
  } else {
    Serial.println("Did not find fingerprint sensor :(");
    while (1);
  }
  Serial.println("Waiting for valid finger...");
}

void loop()                     // run over and over again
{
  getFingerprintIDez();
  delay(50);  //don't ned to run this at full speed.
  int pos = 0;
}


uint8_t getFingerprintID() {
  uint8_t p = finger.getImage();
  switch (p) {
    case FINGERPRINT_OK:
      Serial.println("Image taken");
      break;
    case FINGERPRINT_NOFINGER:
      Serial.println("No finger detected");
      return p;
    case FINGERPRINT_PACKETRECIEVEERR:
      Serial.println("Communication error");
      return p;
    case FINGERPRINT_IMAGEFAIL:
      Serial.println("Imaging error");
      return p;
    default:
      Serial.println("Unknown error");
      return p;
  }

  // OK success!

  p = finger.image2Tz();
  switch (p) {
    case FINGERPRINT_OK:
      Serial.println("Image converted");
      break;
    case FINGERPRINT_IMAGEMESS:
      Serial.println("Image too messy");
      return p;
    case FINGERPRINT_PACKETRECIEVEERR:
      Serial.println("Communication error");
      return p;
    case FINGERPRINT_FEATUREFAIL:
      Serial.println("Could not find fingerprint features");
      return p;
    case FINGERPRINT_INVALIDIMAGE:
      Serial.println("Could not find fingerprint features");
      return p;
    default:
      Serial.println("Unknown error");
      return p;
  }
  
  // OK converted!
  p = finger.fingerFastSearch();
  if (p == FINGERPRINT_OK) {
    Serial.println("Found a print match!");
  } else if (p == FINGERPRINT_PACKETRECIEVEERR) {
    Serial.println("Communication error");
    return p;
  } else if (p == FINGERPRINT_NOTFOUND) {
    Serial.println("Did not find a match");
    return p;
  } else {
    Serial.println("Unknown error");
    return p;
  }   
  
  // found a match!
  
  Serial.print("Found ID #"); Serial.print(finger.fingerID); 
  Serial.print(" with confidence of "); Serial.println(finger.confidence); 

}

// returns -1 if failed, otherwise returns ID #
int getFingerprintIDez() {
   {
  for (pos = 0; pos <= 180; pos += 1) { // goes from 0 degrees to 180 degrees
    // in steps of 1 degree
    myservo.write(pos);              // tell servo to go to position in variable 'pos'
    delay(1500);                       // waits 15ms for the servo to reach the position
  }
  for (pos = 180; pos >= 0; pos -= 1) { // goes from 180 degrees to 0 degrees
    myservo.write(pos);              // tell servo to go to position in variable 'pos'
    delay(1500);                       // waits 15ms for the servo to reach the position
  }
}
  uint8_t p = finger.getImage();
  if (p != FINGERPRINT_OK)  return -1;

  p = finger.image2Tz();
  if (p != FINGERPRINT_OK)  return -1;

  p = finger.fingerFastSearch();
  if (p != FINGERPRINT_OK)  return -1;
  
  // found a match!
  Serial.print("Found ID #"); Serial.print(finger.fingerID); 
  Serial.print(" with confidence of "); Serial.println(finger.confidence);
  return finger.fingerID; 
}

So you decided to mash two pieces of code together and then throw it on the table and then say "Here, make this work".

That's not what we are here for.

If you don't understand how each individual pieces work, then its not our job to figure it for you.

You already posted the SAME question a few days ago: How to modify code - #11 by mazaid - Project Guidance - Arduino Forum

In fact, there have been variations of the same question for this same project for quite some time.
http://forum.arduino.cc/index.php?action=profile;area=showposts;u=402115

Try here