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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 _ztanh(Np: int, gridmin: float, gridmax: float) -> np.ndarray: """ typically call via setupz instead """

    x0 = np.linspace(0, 3.14, Np)  # arbitrarily picking 3.14 as where tanh gets to 99% of asymptote
    return np.tanh(x0)*gridmax+gridmin