Requirements

Write an R function$($s$)$ that performs the Gehan test using the large$-$sample approximation and the permutation test.

Include code that checks if the arguments are valid and returns an error message if there is an invalid argument.

Return a warning message if the large$-$sample test is used when $m<mn>1</mn><mn>0</mn>$ and

Function$($s$)$ should return an object that contains the test statistic, the p$-$value, and the method.

The print method should output: the name of the test $($Gehan$),$ the method used, the test statistic, and the p$-$value.

Comment your code. Including a description of the function$($s$),$ the type and format of the arguments, and a description of the values returned. Your comments should act like a manual for how to use the function. Also include comments in the body of the function that describe what is going on$.$

Apply your function$($s$)$ to the following two datasets. Use the large$-$sample approximation for the first dataset and the permutation test for the second dataset.

Dataset $1$

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Dataset $2$

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