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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 fill_predictive_missing_parameters(self):
 """Fill address with host_name if not already set and define state with initial_state :return: None """

        if hasattr(self, 'host_name') and not hasattr(self, 'address'):
            self.address = self.host_name
        if hasattr(self, 'host_name') and not hasattr(self, 'alias'):
            self.alias = self.host_name
        if self.initial_state == 'd':
            self.state = 'DOWN'
        elif self.initial_state == 'x':
            self.state = 'UNREACHABLE'