Add _image_url variable and function get_image_path to get URL of product image

[PatrickLipka]

Hi,
thank you for providing Python wrappers to the Picnic API!
I have added some simple functionality to get product image URLs. Please review it and consider adding it to upstream if you find it useful.

Best regards,
Patrick

[MikeBrink]

Hi!

Thanks for your contribution. From your code it seems to me that you are not familiar with some pythonic concepts (e.g. default values, type hinting and string formatting). I also am missing a test for your implementation. The coming 3 weeks I am very busy, but I can take a look at this myself then or can help you if you want :)

[PatrickLipka]

Python definitely isn't my go-to language so I'm happy to get hints for improvement. Of course, I dont want to bother you too much with it.
Regarding default values and type hinting I kind of see what you mean and how to improve. When it comes to testing, I'll need to think about it a little bit. Maybe I wil have time to work on it next weekend.

[littleyoda]

So that others do not also have to invest time.
The URL for the images has changed.

https://storefront-prod.{contury}.picnicinternational.com/static/images/{imageID}/medium.png