old_contents: from django.db import models
  
  # from osf_models.models.user import User
  # from osf_models.models.node import Node
  
  
  class Contributor(models.Model):
      read = models.BooleanField(default=False)
      write = models.BooleanField(default=False)
      admin = models.BooleanField(default=False)
      visible = models.BooleanField(default=False)
  
      user = models.ForeignKey('User')
      node = models.ForeignKey('Node')
  
      class Meta:
          unique_together = ('user', 'node')
  
new_contents: from django.db import models
  
  
  class Contributor(models.Model):
      read = models.BooleanField(default=False)
      write = models.BooleanField(default=False)
      admin = models.BooleanField(default=False)
      visible = models.BooleanField(default=False)
  
      user = models.ForeignKey('User')
      node = models.ForeignKey('Node')
  
      class Meta:
          unique_together = ('user', 'node')
  
subject: Remove comments