old_contents: from django.db.models.fields.files import FileField
  
  from easy_thumbnails import signals
  from easy_thumbnails.alias import aliases
  
  
  def find_uncommitted_filefields(sender, instance, **kwargs):
      """
      A pre_save signal handler which attaches an attribute to the model instance
      containing all uncommitted ``FileField``s, which can then be used by the
      :func:`signal_committed_filefields` post_save handler.
      """
      uncommitted = instance._uncommitted_filefields = []
      
      fields = sender._meta.fields
      if kwargs.get('update_fields', None):
          update_fields = set(kwargs['update_fields'])
          fields = update_fields.intersection(fields)
      for field in fields:
          if isinstance(field, FileField):
              if not getattr(instance, field.name)._committed:
                  uncommitted.append(field.name)
  
  
  def signal_committed_filefields(sender, instance, **kwargs):
      """
      A post_save signal handler which sends a signal for each ``FileField`` that
      was committed this save.
      """
      for field_name in getattr(instance, '_uncommitted_filefields', ()):
          fieldfile = getattr(instance, field_name)
          # Don't send the signal for deleted files.
          if fieldfile:
              signals.saved_file.send_robust(sender=sender, fieldfile=fieldfile)
  
  
  def generate_aliases(fieldfile, **kwargs):
      """
      A saved_file signal handler which generates thumbnails for all field,
      model, and app specific aliases matching the saved file's field.
      """
      # Avoids circular import.
      from easy_thumbnails.files import generate_all_aliases
      generate_all_aliases(fieldfile, include_global=False)
  
  
  def generate_aliases_global(fieldfile, **kwargs):
      """
      A saved_file signal handler which generates thumbnails for all field,
      model, and app specific aliases matching the saved file's field, also
      generating thumbnails for each project-wide alias.
      """
      # Avoids circular import.
      from easy_thumbnails.files import generate_all_aliases
      generate_all_aliases(fieldfile, include_global=True)
  
new_contents: from django.db.models.fields.files import FileField
  
  from easy_thumbnails import signals
  
  
  def find_uncommitted_filefields(sender, instance, **kwargs):
      """
      A pre_save signal handler which attaches an attribute to the model instance
      containing all uncommitted ``FileField``s, which can then be used by the
      :func:`signal_committed_filefields` post_save handler.
      """
      uncommitted = instance._uncommitted_filefields = []
  
      fields = sender._meta.fields
      if kwargs.get('update_fields', None):
          update_fields = set(kwargs['update_fields'])
          fields = update_fields.intersection(fields)
      for field in fields:
          if isinstance(field, FileField):
              if not getattr(instance, field.name)._committed:
                  uncommitted.append(field.name)
  
  
  def signal_committed_filefields(sender, instance, **kwargs):
      """
      A post_save signal handler which sends a signal for each ``FileField`` that
      was committed this save.
      """
      for field_name in getattr(instance, '_uncommitted_filefields', ()):
          fieldfile = getattr(instance, field_name)
          # Don't send the signal for deleted files.
          if fieldfile:
              signals.saved_file.send_robust(sender=sender, fieldfile=fieldfile)
  
  
  def generate_aliases(fieldfile, **kwargs):
      """
      A saved_file signal handler which generates thumbnails for all field,
      model, and app specific aliases matching the saved file's field.
      """
      # Avoids circular import.
      from easy_thumbnails.files import generate_all_aliases
      generate_all_aliases(fieldfile, include_global=False)
  
  
  def generate_aliases_global(fieldfile, **kwargs):
      """
      A saved_file signal handler which generates thumbnails for all field,
      model, and app specific aliases matching the saved file's field, also
      generating thumbnails for each project-wide alias.
      """
      # Avoids circular import.
      from easy_thumbnails.files import generate_all_aliases
      generate_all_aliases(fieldfile, include_global=True)
  
subject: Remove an unused import