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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 actualize (self):
 """ Generates actual build instructions. """

        if self.actualized_:
            return

        self.actualized_ = True

        ps = self.properties ()
        properties = self.adjust_properties (ps)


        actual_targets = []

        for i in self.targets ():
            actual_targets.append (i.actualize ())

        self.actualize_sources (self.sources (), properties)

        self.engine_.add_dependency (actual_targets, self.actual_sources_ + self.dependency_only_sources_)

        # FIXME: check the comment below. Was self.action_name_ [1]
        # Action name can include additional rule arguments, which should not
        # be passed to 'set-target-variables'.
        # FIXME: breaking circular dependency
        import toolset
        toolset.set_target_variables (self.manager_, self.action_name_, actual_targets, properties)

        engine = self.manager_.engine ()

        # FIXME: this is supposed to help --out-xml option, but we don't
        # implement that now, and anyway, we should handle it in Python,
        # not but putting variables on bjam-level targets.
        bjam.call("set-target-variable", actual_targets, ".action", repr(self))

        self.manager_.engine ().set_update_action (self.action_name_, actual_targets, self.actual_sources_,
                                                   properties)

        # Since we set up creating action here, we also set up
        # action for cleaning up
        self.manager_.engine ().set_update_action ('common.Clean', 'clean-all',
                                                   actual_targets)

        return actual_targets