Is there any API to manage product attributes ?

[cosmo.spu]

Hello,

I need to modify some products via external php script by using prestashop api. Everything is clear, but flag to product "NEW" isn't. Presta set up this flag, where date of procuct is in some interval. Is there any possibility to set this flag manualy ?

Now I'm setup this flag by this: $product->date_add = 'some old or new date'

I need something like this: $product->is_new = true

Exists somehing like this or exist some clear documentation, where is described this tag ?

Thank you very much for answers and sorry for my bad english :-)