12_review.py

from abc import ABC, abstractmethod

class AbstractEmployee(ABC):
  new_id = 1
  def __init__(self):
    self.id = AbstractEmployee.new_id
    AbstractEmployee.new_id += 1

  @abstractmethod
  def say_id(self):
    pass
# script.py
#
# class User:
#   def __init__(self):
#     self._username = None
# 
#   @property
#   def username(self):
#     return self._username
# 
#   @username.setter
#   def username(self, new_name):
#     self._username = new_name
# 
# class Meeting:
#   def __init__(self):
#     self.attendees = []
#   
#   def __add__(self, employee):
#     print("{} added.".format(employee.username))
#     self.attendees.append(employee.username)
# 
#   def __len__(self):
#     return len(self.attendees)
# 
# class Employee(AbstractEmployee, User):
#     def __init__(self, username):
#       super().__init__()
#       User.__init__(self)
#       self.username = username
# 
#     def say_id(self):
#       print("My id is {}".format(self.id))
#  
#     def say_username(self):
#       print("My username is {}".format(self.username))

from abc import ABC, abstractmethod


class AbstractEmployee(ABC):

    new_id = 1

    def __init__(self):
        self.id = AbstractEmployee.new_id
        AbstractEmployee.new_id += 1

    @abstractmethod
    def say_id(self):
        ...


class User:

    def __init__(self):
        self._username = None

    @property
    def username(self):
        return self._username

    @username.setter
    def username(self, new_name):
        self._username = new_name


class Meeting:

    def __init__(self):
        self.attendees = []

    def __add__(self, employee):
        print(f"{employee.username} added.")
        self.attendees.append(employee.username)

    def __len__(self):
        return len(self.attendees)


class Employee(AbstractEmployee, User):

    def __init__(self, username):
        super().__init__()
        User.__init__(self)
        self.username = username

    def say_id(self):
        print(f"My id is {self.id}")

    def say_username(self):
        print(f"My username is {self.username}")