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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 getChargingVoltage(self):
 """Returns the charging voltage, in volts, or 0.0 of not charging"""

    command = '$GG'
    currentAndVoltage = self.sendCommand(command)
    volts = float(currentAndVoltage[2])/1000
    return volts