If your focus is basically learning Python for Data Science I would greatly recommend start with this coursera course, it's awesome for beginners. I would have recommended datacamp like sites but it tends out that learning through datacamp like sites imparts very sparse knowledge (atleast in my case) . After completing this course I would suggest to jump right into this coursera specialization ( this specialization was best resource for me to learn the same), also keep in mind to do all of its tedious homework assignments.First two courses are pure data analysis and then comes ml . This specialization is very dense and helpful to know many things.
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If you find the 2nd coursera specialization link I shared some difficult go through this pandas course by sentdex. Apart from that if you want to progress to some advance python knowledge corey schafer's matplotlib tutorial is very good(although it's not data science related ,but see this python playlist too).
For someone who might not be able to pay for coursera course, there is an option of financial help(although you can audit the course and do assignments for free). If you need any more links , feel free to comment.