placeholders in Python: placing multiple names in an array

I am a beginner in python and learning “Learn Python: The Complete Python Programming Course” using Udemy. I downloaded Python 3.8. All things were good until I reached placeholders:

for i in arr.

I just want to use the function of placeholders in python and complete the task by placing multiple names in an array
I cannot type any of this. May I know why?

I have contacted the concerned person and he is not responding. I am stuck and can’t move ahead in the learning of the course. Please help ASAP.

Please see the answer to your original post.

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