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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 list_dependents(self, component, dependents=None):
 """ Lists given Component dependents Components. Usage:: True [u'core.tests_component_b'] :param component: Component to retrieve the dependents Components. :type component: unicode :param dependents: Component dependents Components. :type dependents: set :return: Dependent Components. :rtype: list """


        dependents = set() if dependents is None else dependents
        for name, profile in self:
            if not component in profile.require:
                continue

            dependents.add(name)
            self.list_dependents(name, dependents)

        return sorted(list(dependents), key=(self.list_components()).index)