# main class
class UtilitySystems():
    def __init__(self):
        self.potableWater = PotableWater()
        self.wasteWater = WasteWater()
        self.oil = Oil()
        self.naturalGas = NaturalGas()

    def electricPower(self):
        pass

    def communication(self):
        pass

# helper classes
class PotableWater():
    def __init__(self):
        pass

    def facilities(self):
        pass

    def piplines(self):
        pass

class WasteWater():
    def __init__(self):
        pass
    
    def facilities(self):
        pass

    def piplines(self):
        pass

class Oil():
    def __init__(self):
        pass

    def facilities(self):
        pass

    def piplines(self):
        pass

class NaturalGas():
    def __init__(self):
        pass

    def facilities(self):
        pass

    def piplines(self):
        pass
