please help solve these two problem using basic python codes. using sage worksheet is preferred

7. (12 pts. Write a program that inputs an integer n and then outputs an n x n square of *'s such that in odd rows, there are *'s in the odd numbered positions and in the even rows, there are *'s in the even numbered positions. For example on n = 5, your program should output: * ** ** sk * sk * Test your program with n = 15