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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 random_unit(size=3):
 """Return a random unit vector of the given dimension Optional argument: size -- the number of dimensions of the unit vector [default=3] """

    while True:
        result = np.random.normal(0, 1, size)
        length = np.linalg.norm(result)
        if length > 1e-3:
            return result/length