old_contents: from django.http import HttpRequest, HttpResponse
  
  from zerver.models import UserProfile
  from zerver.lib.validator import check_int
  from zerver.lib.response import json_success
  from zerver.lib.request import REQ
  from zerver.lib.attachments import user_attachments, remove_attachment, \
      access_attachment_by_id
  
  
  def list_by_user(request, user_profile):
      # type: (HttpRequest, UserProfile) -> HttpResponse
      return json_success({"attachments": user_attachments(user_profile)})
  
  
  def remove(request, user_profile, attachment_id=REQ(validator=check_int)):
      # type: (HttpRequest, UserProfile, int) -> HttpResponse
      attachment = access_attachment_by_id(user_profile, attachment_id,
                                           needs_owner=True)
      remove_attachment(user_profile, attachment)
      return json_success()
  
new_contents: from django.http import HttpRequest, HttpResponse
  
  from zerver.models import UserProfile
  from zerver.lib.validator import check_int
  from zerver.lib.response import json_success
  from zerver.lib.attachments import user_attachments, remove_attachment, \
      access_attachment_by_id
  
  
  def list_by_user(request, user_profile):
      # type: (HttpRequest, UserProfile) -> HttpResponse
      return json_success({"attachments": user_attachments(user_profile)})
  
  
  def remove(request, user_profile, attachment_id):
      # type: (HttpRequest, UserProfile, int) -> HttpResponse
      attachment = access_attachment_by_id(user_profile, attachment_id,
                                           needs_owner=True)
      remove_attachment(user_profile, attachment)
      return json_success()
  
subject: Remove unnecessary use of REQ.