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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 vector_normalize(mat, max_vec_norm=1.):
 """ Normalize each column vector in mat to length max_vec_norm if it is longer than max_vec_norm """

    assert mat.flags.c_contiguous
    n, m = mat.shape

    vector_normalize_kernel.prepared_call(
        (m, 1, 1), (32, 1, 1),
        mat.gpudata,
        np.float32(max_vec_norm),
        np.int32(m),
        np.int32(n))