polygon - NameError: name 'QGis' is not defined

Question

I am very new to Qgis platform and I used a piece of code that I took from coockbook to iterate over all the polygons in a layer. But it is always showing me an error "NameError: name 'QGis' is not defined". can someone give me a solution for this? If you can explain it would be better because I am just a beginner and I am still trying to understand the inbuilt functions.

this is what I did in my code

this is the extracted code from the cookbook

Answer 1

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