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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 reactive_power_mode(self):
 """ Power factor mode of Load. This information is necessary to make the load behave in an inductive or capacitive manner. Essentially this changes the sign of the reactive power. The convention used here in a load is that: - when `reactive_power_mode` is 'inductive' then Q is positive - when `reactive_power_mode` is 'capacitive' then Q is negative Parameters reactive_power_mode : :obj:`str` or None Possible options are 'inductive', 'capacitive' and 'not_applicable'. In the case of 'not_applicable' a reactive power time series must be given. Returns ------- :obj:`str` In the case that this attribute is not set, it is retrieved from the network config object depending on the voltage level the load is in. """

        if self._reactive_power_mode is None:
            if isinstance(self.grid, MVGrid):
                self._reactive_power_mode = self.grid.network.config[
                    'reactive_power_mode']['mv_load']
            elif isinstance(self.grid, LVGrid):
                self._reactive_power_mode = self.grid.network.config[
                    'reactive_power_mode']['lv_load']

        return self._reactive_power_mode