what are the issues with this code "from buildhat import Motor
from gpiozero import SmoothedInputDevice
from gpiozero import DigitalInputDevice
from gpiozero import HoldMixin
import time
import sys

# Line Finder Import
class LineFinder(SmoothedInputDevice):
    """
    Simple Line Finder Class

    Args:
        pin(int): the digital pin to which the line finder is assigned
        pull_up(bool): whether the button is set to pull up or down. This impacts whether the 
            button returns a 0 or 1 when pressed and must be set to false for the wiring setup of 
            the base hat.
        sample_rate(float): The number of values to read from the device per second. Defaults to 100.
    """
    def __init__(self, pin=None, *, pull_up=False, active_state=None,
                 queue_len=1, sample_rate=5, threshold=0.5, partial=False,
                 pin_factory=None):
        super().__init__(
            pin, pull_up=pull_up, active_state=active_state,
            threshold=threshold, queue_len=queue_len,
            sample_wait=1 / sample_rate, partial=partial,
            pin_factory=pin_factory)
        self._queue.start()

    @property
    def value(self):
        """
        Returns a value representing the average of the queued values. This
        is 0 for black under the sensor, and 1 for white under the sensor.
        """
        val = super().value
        print(f"Sensor Value: {'White (1)' if val == 1 else 'Black (0)'}")
        return val
    
    @property
    def line_detected(self):
        detected = not self.is_active
        print(f"Line Detected: {'Black' if detected else 'White'}")
        return detected

# Hall Sensor Import
class HallSensor(HoldMixin, DigitalInputDevice):
    """
    Simple Hall Sensor Class

    Args:
        pin(int): the digital pin to which the sensor is assigned
        pull_up(bool): whether the sensor is set to pull up or down. This impacts whether the 
            sensor returns a 0 or 1 when near a magnet and must be set to false for the wiring 
            setup of the base hat.
        bounce_time(float): The length of time (in seconds) after the button is pressed during which 
            new inputs are ignored. This minimizes 'bouncy' signals, where the output of the button
            changes rapidly as it is being pressed. The base time for this is 1 second.
    """
    def __init__(self, pin=None, *, pull_up=True, active_state=None,
                 bounce_time=None, pin_factory=None):
        super().__init__(
            pin, pull_up=pull_up, active_state=active_state,
            bounce_time=bounce_time, pin_factory=pin_factory)

    @property
    def value(self):
        """
        Returns 1 if the button is currently pressed, and 0 if it is not.
        """
        return super().value

# Main Function
def main():
    lPin = 18
    rPin = 26
    halPin = 24

    print("System booting")
    lMotor = Motor('A')
    backMotor = Motor('C')
    motor = Motor('D')

    rLineReader = LineFinder(rPin)
    lLineReader = LineFinder(lPin)
    
    hallSen = HallSensor(halPin)

    lineValueR = 1
    lineValueL = 1
    
    halValue = 0
    halCounter = 0
    
    # Change this value to determine which landing zone the robot should go over
    landZone = 1
    readyToDeliver = 0
    motor_activated = False  # Initialize the motor activation flag

    try:
        while True:
            try:
                lineValueR = rLineReader.line_detected
                lineValueL = lLineReader.line_detected
                hallValue = hallSen.value

                print(f"Right Sensor: {lineValueR}, Left Sensor: {lineValueL}")
                print(f"Hall Sensor: {hallValue}")
                print(f"Magnet count: {halCounter}")
                
                lMotor.start(40)
                
                # Incrementing counter if magnet is detected
                if hallValue:
                    halCounter += 1
                    
                # If proper magnet count is reached, turn robot to deliver
                if halCounter == landZone:
                    readyToDeliver = 1
                    lMotor.stop()
                    backMotor.run_for_rotations(0.2) 
                    time.sleep(0.3)
                    lMotor.start(35)
                    time.sleep(0.3)
                    lMotor.stop()
                    time.sleep(0.2)
                    backMotor.run_for_rotations(-0.2)
                    
                # Returns False over white, True over black
                if lineValueR and not lineValueL:
                    lMotor.stop()
                    backMotor.run_for_rotations(0.14)  # was 0.125
                    time.sleep(0.3)
                    lMotor.start(45)
                    time.sleep(1)
                    lMotor.stop()
                    time.sleep(0.2)
                    backMotor.run_for_rotations(-0.14)

                elif not lineValueR and lineValueL:
                    lMotor.stop()
                    backMotor.run_for_rotations(-0.14)
                    time.sleep(0.3)
                    lMotor.start(45)
                    time.sleep(1)
                    lMotor.stop()
                    time.sleep(0.2)
                    backMotor.run_for_rotations(0.14)

                # Code for magnets & moving the cargo motor
                if hallValue != 0:
                    print("NOT DETECTED - Motor OFF")
                    motor.stop()
                else:
                    if not motor_activated:
                        print("DETECTED - Activating Motor")
                        motor_activated = True  # Set the flag to prevent re-activation
                        motor.run_for_rotations(0.18, speed=100)
                        motor.stop()
                        time.sleep(0.8)
                        motor.run_for_rotations(-0.18, speed=100)
                    else:
                        print("DETECTED - Motor has already been activated. Ignoring further detections.")
                        exit()
            
            except IOError:
                print("Error reading")
                backMotor.stop()
                lMotor.stop()
                break
    except KeyboardInterrupt:
        print("Ending")
        backMotor.stop()
        lMotor.stop()

if __name__ == '__main__':
    main()
"