class Voltmeter:
  def __init__(self,_truevoltage,_noiselevel):
    self.truevoltage = _truevoltage
    self.noiselevel = _noiselevel
  def GetVoltage(self):
    return self.truevoltage
  def GetVoltageWithNoise(self):
    return random.gauss(self.GetVoltage(),self.noiselevel)
