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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 ylogydu(y, u):
 """ tool to give desired output for the limit as y -> 0, which is 0 Parameters y : array-like of len(n) u : array-like of len(n) Returns ------- np.array len(n) """

    mask = (np.atleast_1d(y)!=0.)
    out = np.zeros_like(u)
    out[mask] = y[mask] * np.log(y[mask] / u[mask])
    return out