Videos and Online-Courses
A great resource for valuable video courses is learning.oreilly.com – which can be accessed for free with the h_da single-sign-on. I especially recommend the videos by Arianne Dee, who is a very thoughtful instructor. I did her course ‘Next Level Python’ but I guess the “Introduction to Python: Learn How to Program Today with Python” is also worth taking a look. An advanced course on using Python for data visualization is this one by AI Sciences.
Udemy is a commercial platform offering a lot of courses on Python. I definitely recommend the introduction by my former colleague René Brunner (in German Language), which was actually the first course I enrolled for. It has a slow pace and is very comprehensive. If you like I can ask him for a discount.
A great course for understanding the advanced concept of Sentiment Analysis is Applied Text Mining and Sentiment Analysis with Python by Data Analyst Benjamin Termonia. He not only offers a great introduction to the concept but also a step-by-step tutorial on building/training your own Sentiment Analysis environment.
Code Academy is a very innovative commercial platform that is totally worth its high price of $149.99/year for students as it provides clearly structured lessons and learning paths for different fields, an interactive online learning editor, videos, cheat sheets etc. It’s definitely worth applying for the free trial period.
Finally, the resource python for humanities offers great tutorials on advanced methods like sentiment analysis and network graphs. This is also your first address when it comes to using Python in a scientific context. The author is a fellow at the Smithsonian and offers great insights into methods like ML, Topic Modeling, Sentiment Analysis etc.
Other Ressources
There are plenty of sites to look up basic functions and test-run Python's core concepts. For starters, I recommend w3-schools.
If you have concrete questions about your code, StackOverflow is the place to go. If you are searching for discussion around libraries, check GitHub.