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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 free_memory(cls, exclude=None):
 """Free global annotation memory."""


        annotations_in_memory = Annotation.__ANNOTATIONS_IN_MEMORY__

        exclude = () if exclude is None else exclude

        for annotation_cls in list(annotations_in_memory.keys()):

            if issubclass(annotation_cls, exclude):
                continue

            if issubclass(annotation_cls, cls):
                del annotations_in_memory[annotation_cls]