from numpy import array, full, fill_diagonal, fliplr

count = int(input("введите число строк в матрице (nxn): "))

if count%2!=1:
    count+=1
Array = full((count, count), ".")
new_diag = ["*" for _ in range(count)]
fill_diagonal(Array, new_diag)
Array = fliplr(Array)
fill_diagonal(Array, new_diag)
Array = fliplr(Array)
print (Array)