Is it possible to use the bot and ask the user to upload an image?

Hi Team,

With regards to this post https://snatchbot.me/amp/blog/150/upload-to-a-chatbot . We want to know how to use this upload capability. In this post you have explained all the uses of it but we cannot find how to use this in the documentations. Can you please help to provide the required docs for this so that we can use this uploading feature.

We want to provide the user a button to upload receipt. When the user clicks on the upload button it should open the browsing window from the user's local system and they should be able to upload an image and we should be able to capture this image using our backend service.

Thanks