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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 normalise(v):
 """Normalise columns of matrix. Parameters v : array_like Array with columns to be normalised Returns ------- vnrm : ndarray Normalised array """


    vn = np.sqrt(np.sum(v**2, 0))
    vn[vn == 0] = 1.0
    return np.asarray(v / vn, dtype=v.dtype)