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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 depth_soil_conductivity(self, value=None):
 """Corresponds to IDD Field `depth_soil_conductivity` Args: value (float):
 value for IDD Field `depth_soil_conductivity` Unit: W/m-K, if `value` is None it will not be checked against the specification and is assumed to be a missing value Raises: ValueError: if `value` is not a valid value """

        if value is not None:
            try:
                value = float(value)
            except ValueError:
                raise ValueError(
                    'value {} need to be of type float '
                    'for field `depth_soil_conductivity`'.format(value))

        self._depth_soil_conductivity = value