I am writing an application with Python, that will look for updates online(let us refer to it as A) every 2 hrs, if you will find new posts, it'll download the pictures within the publish and publish these to another website(refer to it as B), then remove individuals images. Site B provide API for upload images with description, that is like:
upload(image_path, description), where image_path may be the path from the image on your pc.
Now I have finished the application, and I am attempting to make it operate on Google Application Engine(because my computer will not run 7x24), however it appears that GAE will not allow you to write files on its file system.
How do i solve this issue? Or exist other options free of charge Python hosting and supplying "cron job" feature?

GAE includes a BlobStore API, which could work virtually like a file storage, but most likely it isn't that which you whant. Really, the best answer is dependent on which type of API you are using - it might support file-like objects, which means you could pass urllib response object, or accept Web addresses, or a lot of other interesting features

You should not want to use temporary storage whatsoever - just download the look with urlfetch into memory, then use another urlfetch to upload it towards the destination site.