Another suggestion is Amazon Web Services, specifically two services – IoT Core and Elastic Beanstalk. These options will provide you with immense flexibility and a near-endless number of options when it comes to creating IoT applications. IoT Core is Amazon's IoT platform where you can create dashboards, workflows, and integrations, while Elastic Beanstalk is their cloud platform where you can host your own programs – including Python – in the cloud.
Amazon Web Services is an advanced development platform, so you will need to invest weeks into learning how it works and how to build and deploy applications using it, but I can promise you that you will learn a lot during the process! Plus, their documentation and tutorials are very high quality.
Amazon IoT Core: https://aws.amazon.com/iot-core.
Amazon Elastic Beanstalk: https://aws.amazon.com/elasticbeanstalk.