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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 check_ethinca_against_bank_params(ethincaParams, metricParams):
 """ Cross-check the ethinca and bank layout metric calculation parameters and set the ethinca metric PN order equal to the bank PN order if not previously set. Parameters ethincaParams: instance of ethincaParameters metricParams: instance of metricParameters """

    if ethincaParams.doEthinca:
        if metricParams.f0 != metricParams.fLow:
            raise ValueError("If calculating ethinca metric, f0 and f-low "
                             "must be equal!")
        if ethincaParams.fLow is not None and (
                ethincaParams.fLow != metricParams.fLow):
            raise ValueError("Ethinca metric calculation does not currently "
                             "support a f-low value different from the bank "
                             "metric!")
        if ethincaParams.pnOrder is None:
            ethincaParams.pnOrder = metricParams.pnOrder
    else: pass