sensors.py

const int buttonPin1 = 2;     // the number of the pushbutton pin
const int ledPin1 =  8;      // the number of the LED pin
const int buttonPin2 = 3;
const int ledPin2 = 9;
const int buttonPin3 = 4;
const int ledPin3 = 10;
const int ButtonPinMaster = 5;

// variables will change:
int buttonState1 = 0;         // variable for reading the pushbutton status
int buttonState2 = 0; 
int buttonState3 = 0; 
int buttonStateMaster = 0; 

void setup() {
  Serial.begin(9600);
  // initialize the LED pin as an output:
  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  pinMode(ledPin3, OUTPUT);
  // initialize the pushbutton pin as an input:
  pinMode(buttonPin1, INPUT);
  pinMode(buttonPin2, INPUT);
  pinMode(buttonPin3, INPUT);
  pinMode(ButtonPinMaster, INPUT);
}

void loop() {
  // read the state of the pushbutton value:
  buttonState1 = digitalRead(buttonPin1);
  buttonState2 = digitalRead(buttonPin2);
  buttonState3 = digitalRead(buttonPin3);
  buttonStateMaster = digitalRead(ButtonPinMaster);

  Serial.println(buttonState1);
  // check if the pushbutton is pressed. If it is, the buttonState is HIGH:
  if(buttonStateMaster == HIGH) {
    digitalWrite(ledPin1, HIGH);
    digitalWrite(ledPin2, HIGH);
    digitalWrite(ledPin3, HIGH);
  } else {
    digitalWrite(ledPin1, buttonState1);
    digitalWrite(ledPin2, buttonState2);
    digitalWrite(ledPin3, buttonState3);
  }
}