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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def make_grid(xx, yy):
 """ Returns two n-by-n matrices. The first one contains all the x values and the second all the y values of a cartesian product between `xx` and `yy`. """

    n = len(xx)
    xx, yy = np.meshgrid(xx, yy)
    grid = np.array([xx.ravel(), yy.ravel()]).T
    x = grid[:, 0].reshape(n, n)
    y = grid[:, 1].reshape(n, n)
    return x, y