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.
Print(sen%(“i”))

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.

If the answer was unsatisfactory, please reply to the answer, rather than repost your question.