didnt understood the key concept.
Didnt understood the key concept
Hello @lipika, the key is used to pass on the comparator function, or we can say it allows us to set the condition on which condition we need to sort the data.
So as if we use,
key = lambda x : x[1]
This means we are providing the condition that we need to sort this data based on the names, not based on the marks.
By default it is key = lambda x : x[0]
I hope you understand this. In case if there is any query pls let me know.
And if it is clear to you pls mark it as resolve and feel free to provide the feedback.
Thanks 
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