text: # from project.customer import Customer
  # from project.equipment import Equipment
  # from project.exercise_plan import ExercisePlan
  # from project.subscription import Subscription
  # from project.trainer import Trainer
  #
  #
  class Gym:
      def __init__(self):
          self.customers = []
          self.trainers = []
          self.equipment = []
          self.plans = []
          self.subscriptions = []
  
      def add_customer(self, customer):
          if customer not in self.customers:
              self.customers.append(customer)
  
      def add_trainer(self, trainer):
          if trainer not in self.trainers:
              self.trainers.append(trainer)
  
      def add_equipment(self, equipment):
          if equipment not in self.equipment:
              self.equipment.append(equipment)
  
      def add_plan(self, plan):
          if plan not in self.plans:
              self.plans.append(plan)
  
      def add_subscription(self, subscription):
          if subscription not in self.subscriptions:
              self.subscriptions.append(subscription)
  
      def subscription_info(self, subscription_id: int):
          subscription = [s for s in self.subscriptions if s.id == subscription_id][0]
          customer = [c for c in self.customers if c.id == subscription.customer_id][0]
          trainer = [t for t in self.trainers if t.id == subscription.trainer_id][0]
          equipment = [e for e in self.equipment if e.id == subscription.exercise_id][0]
          plan = [p for p in self.plans if p.id == subscription.exercise_id][0]
  
          result = f'{subscription.__repr__()}\n' \
                   f'{customer.__repr__()}\n' \
                   f'{trainer.__repr__()}\n' \
                   f'{equipment.__repr__()}\n' \
                   f'{plan.__repr__()}'
          return result
  #
  # from project.customer import Customer
  # from project.equipment import Equipment
  # from project.exercise_plan import ExercisePlan
  # # from project.gym import Gym
  # from project.subscription import Subscription
  # from project.trainer import Trainer
  #
  # customer = Customer("John", "Maple Street", "john.smith@gmail.com")
  # equipment = Equipment("Treadmill")
  # trainer = Trainer("Peter")
  # subscription = Subscription("14.05.2020", 1, 1, 1)
  # plan = ExercisePlan(1, 1, 20)
  #
  # gym = Gym()
  #
  # gym.add_customer(customer)
  # gym.add_equipment(equipment)
  # gym.add_trainer(trainer)
  # gym.add_plan(plan)
  # gym.add_subscription(subscription)
  #
  # print(Customer.get_next_id())
  #
  # print(gym.subscription_info(1))
  