__call__

class T(object):
    
    def __init__(self):
        self.times = 0

    def __call__(self):
        self.times += 1
        return "Add"

t = T()
print(t())      # 调用 __call__ 函数
print(t.times)
print(t())      # 调用 __call__ 函数
print(t.times)

# Add
# 1
# Add
# 2