waitTime=0.5
def is_ava():
    waitTime = waitTime + 0.1
    print waitTime
if __name__ == '__main__':
    is_ava()
Why UnboundLocalError: local variable 'waitTime' referenced before assignment , I have declared waitTime.
Python version: 2.7
waitTime=0.5
def is_ava():
    waitTime = waitTime + 0.1
    print waitTime
if __name__ == '__main__':
    is_ava()
Why UnboundLocalError: local variable 'waitTime' referenced before assignment , I have declared waitTime.
Python version: 2.7
To modify global variable, you need to declare it inside the function as a global variable:
waitTime=0.5
def is_ava():
    global waitTime  # <--------
    waitTime = waitTime + 0.1
    print waitTime
if __name__ == '__main__':
    is_ava()
