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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 class_name_for_annotation_type(annotation_type, ns=None):
 """ Same as class_name_for_data_type, but works with annotation types. """

    assert isinstance(annotation_type, AnnotationType)
    name = fmt_class(annotation_type.name)
    if ns:
        return prefix_with_ns_if_necessary(name, annotation_type.namespace, ns)
    return name