old_contents: from django.db import models
  
  class Student(models.Model):
      """Student Model"""
  
      class Meta(object):
          verbose_name = "Студент"
          verbose_name_plural = "Студенти"
  
  
      first_name = models.CharField(
          max_length=256,
          blank=False,
          verbose_name='Ім’я')
  
      last_name = models.CharField(
          max_length=256,
          blank=False,
          verbose_name='Прізвище')
  
      middle_name = models.CharField(
          max_length=256,
          blank=True,
          verbose_name='По-батькові',
          default='')
  
      birthday = models.DateField(
          blank=False,
          verbose_name='Дата народження',
          null=True)
  
      photo = models.ImageField(
          blank=True,
          verbose_name='Фото',
          null=True)
  
      ticket = models.CharField(
          max_length=256,
          blank=False,
          verbose_name='Білет')
  
      notes = models.TextField(
          blank=True,
          verbose_name='Додаткові нотатки')
  
      def __str__(self):
          return "%s %s" % (self.last_name, self.first_name)
new_contents: from django.db import models
  
  class Student(models.Model):
      """Student Model"""
  
      class Meta(object):
          verbose_name = "Студент"
          verbose_name_plural = "Студенти"
  
  
      first_name = models.CharField(
          max_length=256,
          blank=False,
          verbose_name='Ім’я')
  
      last_name = models.CharField(
          max_length=256,
          blank=False,
          verbose_name='Прізвище')
  
      middle_name = models.CharField(
          max_length=256,
          blank=True,
          verbose_name='По-батькові',
          default='')
  
      birthday = models.DateField(
          blank=False,
          verbose_name='Дата народження',
          null=True)
  
      photo = models.ImageField(
          blank=True,
          verbose_name='Фото',
          null=True)
  
      ticket = models.CharField(
          max_length=256,
          blank=False,
          verbose_name='Білет')
  
      notes = models.TextField(
          blank=True,
          verbose_name='Додаткові нотатки')
  
      def __str__(self):
          return "%s %s" % (self.last_name, self.first_name)
  
  class Group(models.Model):
      """Group Model"""
      
      class Meta(object):
          verbose_name = 'Група'
          verbose_name_plural = 'Групи'
  
      title = models.CharField(
          max_length=256,
          blank=False,
          verbose_name='Назва')
  
      leader = models.OneToOneField('Student',
          verbose_name='Староста',
          blank=True,
          null=True,
          on_delete=models.SET_NULL)
          
      notes = models.TextField(
          blank=True,
          verbose_name='Додаткові нотатки')
  
      def __str__(self):
          if self.leader:
              return '%s (%s %s)' % (self.title, self.leader.first_name,
                                                 self.leader.last_name)
          else:
              return '%s' % self.title          
subject: add Group model