def METHOD_NAME(self):
    """
    Test value obtained when arbitrary z_mean is passed
    """
    methodVal = coupling_parameter(
        self.T,
        self.n_e,
        self.particles,
        z_mean=self.z_mean,
        V=np.nan * u.m / u.s,
        method="classical",
    )
    testTrue = np.isclose(self.True_zmean, methodVal, rtol=1e-1, atol=0.0)
    errStr = f"Coupling parameter should be {self.True_zmean} and not {methodVal}."
    assert testTrue, errStr