ERROR: 'categories'

Traceback (most recent call last):
  File "/var/www/desktop.in.ua/core/app.py", line 104, in run
    self.view()
  File "/var/www/desktop.in.ua/core/app.py", line 166, in view
    _data = method_handler(self.Request)
  File "/var/www/desktop.in.ua/sites/desktopinua/views/catalog.py", line 198, in product
    data['category'] = CategoryEntity.get(id=data['product']['categories'][0])
KeyError: 'categories'