Working with timeouts

timerdemo.py

# Assumption is that at this point, imports and keypad initialization have been done

timeout = 15  # Seconds, until entry is reset
entry_begin = 0  # Timestamp when entry began
sequence = ""  # Entrysequence with keys appended
pin = "1234"
idle_time = 0.05  # 50 ms, should work fine

while True:
    now = time.time()
    entry = kp.getkey()
    
    if entry is not None:
        sequence += entry
        entry = None
        entry_begin = time.now()
        
    if entry_begin + timeout >= now:
        print("Timeout")
        sequence = []
        entry_begin = 0
        
    if sequence == pin:
        print("Yay")
        
    # To idle loop:
    time.sleep(idle_time)