old_contents: # django
  from wsgiref.util import FileWrapper
  from django.http import HttpResponse, HttpResponseBadRequest
  from django.utils.translation import ugettext as _
  # project
  from db_file_storage.storage import DatabaseFileStorage
  
  
  storage = DatabaseFileStorage()
  
  
  def get_file(request, add_attachment_headers):
      name = request.GET.get('name')
  
      try:
          _file = storage.open(name)
      except Exception:
          return HttpResponseBadRequest(_('Invalid request'))
  
      response = HttpResponse(
          FileWrapper(_file),
          content_type=_file.mimetype
      )
  
      if add_attachment_headers:
          response['Content-Disposition'] = \
              'attachment; filename=%(name)s' % {'name': _file.filename}
  
      return response
  
new_contents: # django
  from wsgiref.util import FileWrapper
  from django.http import HttpResponse, HttpResponseBadRequest
  from django.utils.translation import ugettext as _
  # project
  from db_file_storage.storage import DatabaseFileStorage
  
  
  storage = DatabaseFileStorage()
  
  
  def get_file(request, add_attachment_headers):
      name = request.GET.get('name')
  
      try:
          _file = storage.open(name)
      except Exception:
          return HttpResponseBadRequest(_('Invalid request'))
  
      response = HttpResponse(
          FileWrapper(_file),
          content_type=_file.mimetype
      )
      response['Content-Length'] = _file.tell()
      if add_attachment_headers:
          response['Content-Disposition'] = \
              'attachment; filename=%(name)s' % {'name': _file.filename}
  
      return response
  
subject: Set Content-Length header in get_file view