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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 _handle_class_instance(self, klass):
 """ handles class instances. If a class is blacklisted, returns. If uniuqe_instances is True and the class is unique, instantiates the class and adds the new object to plugins. If not unique_instances, creates and adds new instance to plugin state """

        if (klass in self.blacklisted_plugins or not
                self.instantiate_classes or
                klass == IPlugin):
            return
        elif self.unique_instances and self._unique_class(klass):
            self.plugins.append(klass())
        elif not self.unique_instances:
            self.plugins.append(klass())