old_contents: from django.contrib.auth.models import User
  from django.db import models
  
  from service_and_process.models import MasterProcess
  
  
  class MasterSection(models.Model):
      CHOICES = ((1, 'Laundry'),
                 (2, 'Kitchen'))
      label = models.IntegerField(choices=CHOICES)
  
      def __str__(self):
          return "{}. {}".format(self.id, self.get_label_display())
  
  
  class InternalUser(models.Model):
      user = models.OneToOneField(User)
      parent = models.ForeignKey('self')
      section = models.ForeignKey(MasterSection)
      # present_trainer = models.ManyToManyField('self', through='production_system.MappingTrainerTraineeTask')
  
  
  class Customer(models.Model):
      name = models.TextField()
      address = models.TextField()
      phone_number = models.IntegerField()
      email_id = models.EmailField()
  
  
  
new_contents: from django.contrib.auth.models import User
  from django.db import models
  
  
  class MasterSection(models.Model):
      label = models.TextField()
  
      def __str__(self):
          return "{}. {}".format(self.id, self.label)
  
  
  class InternalUser(models.Model):
      user = models.OneToOneField(User)
      parent = models.ForeignKey('self')
      section = models.ForeignKey(MasterSection)
      # present_trainer = models.ManyToManyField('self', through='production_system.MappingTrainerTraineeTask')
  
  
  class Customer(models.Model):
      name = models.TextField()
      address = models.TextField()
      phone_number = models.IntegerField()
      email_id = models.EmailField()
  
  
  
subject: remove choices