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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 extensions(self, component):
 """Return a list of components that declare to implement the extension point interface. """

        classes = ComponentMeta._registry.get(self.interface, ())
        components = [component.compmgr[cls] for cls in classes]
        return [c for c in components if c]