If you are looking to learn to code or pick up a new programming language in 2020, look no further than Python.
One of the world's most popular open-source programming language has it all - simplicity, reliability, and ease of use. Your efforts towards web development and data science go as far as you can take them when you use Python. Regarding web development, you can create highly-scalable web applications using frameworks like Django and Flask. When it comes to data science, your Python prowess is multiplied with cutting-edge libraries like PyTorch and Tensorflow.
While many other programming languages exist, I am convinced that Python provides the most return on your learning investment for Web Development and Data Science.