No matter how many times I recreated the instance, the variable I intended to create with __init__ () did not change, and I was addicted to it for months.

Conclusion

I've been misunderstanding since I started writing python

class H:
  val = 1        <-------this is
  
  def __init__(self):
    self.val = 1        <-------I thought it was the same as this

It was really like this

class H:
  val = 1        <-------Class variables
  
  def __init__(self):
    self.val = 1        <-------Instance variables

test code

import datetime, time

#Class variables
class A:
    t = datetime.datetime.today()          #<-----------------#Class variable: No matter how many instances you create, it doesn't change! !!

class B:
    def __new__(cls):                      # <----------------# __new__Instance variables
        self = object.__new__(cls)
        # print('__new__ :', str(id(self)))
        self.t = datetime.datetime.today()
        return self

class C:
    def __init__(self):                 # <----------------# __init__Instance variables
        self.t = datetime.datetime.today()

class D:
    def __call__(self):                 # <----------------# __call__Instance variable is class name()Called by. instance.__call__()Feeling to save labor.
        return datetime.datetime.today()

def start():
    print("-start")
    print(datetime.datetime.today())

    print("-A")
    instance = A()
    print(A.t)           #Only the class variable can be called directly from the class, not the instance
    print(instance.t)    #Get from instance<-----------Common value for different instances (fixed by the number when class was first called)

    print("-B")
    instance = B()
    print(instance.t)

    print("-C")
    instance = C()
    print(instance.t)

    print("-D")
    instance = D()
    print(instance())    # <---------------- __call__Is the class name()Called by. instance.__call__()Feeling to save labor.

##############################################################
if __name__ == "__main__":

    start()
    print("=========================================")
    time.sleep(1)
    start()

result

I'm recreating an instance

-start
2020-01-30 14:29:24.227419
-A
2020-01-30 14:29:24.227217             <-----------here
2020-01-30 14:29:24.227217
-B
2020-01-30 14:29:24.227470
-C
2020-01-30 14:29:24.227494
-D
2020-01-30 14:29:24.227516
=========================================
-start
2020-01-30 14:29:25.230648
-A
2020-01-30 14:29:24.227217           <-----------Here is the same orz
2020-01-30 14:29:24.227217
-B
2020-01-30 14:29:25.230766
-C
2020-01-30 14:29:25.230833
-D
2020-01-30 14:29:25.230877

Others are different. The class variable was such a thing ...

Style to step through with full power

** Notes on using class variables ** When accessing class variables, you should avoid accessing them like "instance.class variables" or "self.class variables" unless you have a specific reason to do so. In Python, you can create an instance variable from an instance object, and you may unintentionally hide a class variable with an instance variable. https://uxmilk.jp/41600

We are doing our best in various places. Howl ~. It was a mess ...