How to use the "class" function (Python)

class calculate:
    def add(self,abc):    # self is a boilerplate when using classes
        a=abc+1
        print(a)

cal=calculate()    #Define the class calculate as cal.
cal.add(10)    # Call the add function in the class. Assign 10 to abc.

    → 11

cal=calculate().add(10)   # This way of writing is also fine. However, it will only be called once.

    → 11

class calculate:
    def add(self):
        self.a=1+1  # The variable can be used in other functions by setting it as "self".
        print(self.a)

    def sub(self):
        b=self.a-1
        print(b)

cal=calculate()
cal.add()
cal.sub()

 → 2
     1

class calculate:
    def __init__(self, c): # Initial value assignment function
        self.c = c
        self.d = 20

    def add(self,d):
        self.a=self.c+d
        print(self.a)

    def sub(self):
        b=self.a-1
        print(b)

cal=calculate(10) # Assign 10 to c in the initial value assignment function
print(vars(cal))

    → {'c': 10, 'd': 20} # print(cal.c) prints only c

cal.add(5) # Assign 5 to the variable d in the add function

    → 15

cal.sub()

    → 14

cal.d #You can also call variables

    → 20

class caladd:
    def __init__(self, c):
        self.c = c

    def add(self,d):
        self.a=self.c+d
        print(self.a)

class calsub(caladd):# Define the initial value of the caladd class
    def sub(self):
        super(calsub,self).add(5) # Executes the add function of caladd. calsub and self can be omitted.
        b=self.a-1
        print(b)

cal=calsub(10) # Assign 10 to the initial value of the caladd class
cal.sub()

 → 15
    14