class Counter:
    instance_num = 0

    def __init__(self):
        Counter.instance_num += 1

    def __del__(self):
        Counter.instance_num -= 1

    def get_instance_num(self):
        print('instance num:%d' % Counter.instance_num)

82480d75ff387ce2729f5720ef86b27bb97aed66
class Counter:
    <mask token>
    <mask token>
    <mask token>
    <mask token>

class Counter:
    <mask token>

    def __init__(self):
        Counter.instance_num += 1

    def __del__(self):
        Counter.instance_num -= 1
    <mask token>

class Counter:
    <mask token>

    def __init__(self):
        Counter.instance_num += 1

    def __del__(self):
        Counter.instance_num -= 1

    def get_instance_num(self):
        print('instance num:%d' % Counter.instance_num)

class Counter:
    instance_num = 0

    def __init__(self):
        Counter.instance_num += 1

    def __del__(self):
        Counter.instance_num -= 1

    def get_instance_num(self):
        print('instance num:%d' % Counter.instance_num)
