How many hours does it take to learn data science?

Hi,

I am beginner in Data Science and machine learning field. I am searching for the tutorials to learn:

How many hours does it take to learn data science?

Try to provide me good examples or tutorials links so that I can learn the topic "How many hours does it take to learn data science?". Also tell me which is the good training courses in Machine Learning, Artificial Intelligence and Data Science for beginners.

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