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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 calcMassFromMz(mz, charge):
 """Calculate the mass of a peptide from its mz and charge. :param mz: float, mass to charge ratio (Dalton / charge) :param charge: int, charge state :returns: non protonated mass (charge = 0) """

    mass = (mz - maspy.constants.atomicMassProton) * charge
    return mass