T011: Querying online API webservices. We give a broad introduction on how to programmatically use online webservices from Python with a focus on REST services and web scraping. The usage of several libraries is demonstrated; e.g. we use requests to retrieve content from UniProt , bravado to generate a Python client for any API -exemplified for the KLIFS database and its RESTful API -, and Beautiful Soup to scrape (parse) HTML content from the web. Next, this newly gained knowledge is applied to interact with the KLIFS and PubChem databases.