Arduino code to display a different color LED based on what number it's given.

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int incoming = 0;
int REDPin = 4;    // RED pin 
int GREENPin = 5;  // GREEN pin 
int BLUEPin = 6;   // BLUE pin 

void setup() {
  // setup serial and led pins
  Serial.begin(9600);
  pinMode(REDPin, OUTPUT);
  pinMode(GREENPin, OUTPUT);
  pinMode(BLUEPin, OUTPUT);
}

void loop() {
  
  /* if data */
  if(Serial.available() > 0) {
    
    /* get number from python*/
    incoming = Serial.read();
    Serial.print(incoming, DEC);
    Serial.print('\n');
    
    /* light based on number */
    if(incoming > 10) {
        lightRed(); 
    } else if(incoming > 5){
        lightYellow();
    } else if(incoming > 0){
        lightGreen();
    } else {
        lightsOff();
    }
    
  }
  
  delay(2000);
  
}

void lightRed() {
   analogWrite(REDPin, 255); 
   analogWrite(GREENPin, 0);
   analogWrite(BLUEPin, 0);
}

void lightGreen() {
   analogWrite(REDPin, 0); 
   analogWrite(GREENPin, 255);
   analogWrite(BLUEPin, 0);
}

void lightBlue() {
   analogWrite(REDPin, 0); 
   analogWrite(GREENPin, 130);
   analogWrite(BLUEPin, 255);
}

void lightYellow() {
   analogWrite(REDPin, 255); 
   analogWrite(GREENPin, 230);
   analogWrite(BLUEPin, 0);
}

void lightsOff() {
  analogWrite(REDPin, 0);
  analogWrite(GREENPin, 0);
  analogWrite(BLUEPin, 0);
}