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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 z2r(z):
 """ Function that calculates the inverse Fisher z-transformation Parameters z : int or ndarray Fishers z transformed correlation value Returns result : int or ndarray Correlation value """

    with np.errstate(invalid='ignore', divide='ignore'):
        return (np.exp(2 * z) - 1) / (np.exp(2 * z) + 1)