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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 transform_to_3d(points,normal,z=0):
 """Project points into 3d from 2d points."""

    d = np.cross(normal, (0, 0, 1))
    M = rotation_matrix(d)
    transformed_points = M.dot(points.T).T + z
    return transformed_points