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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 register(class_):
 """Registers a new word embedding evaluation function. Once registered, we can create an instance with :func:`~gluonnlp.embedding.evaluation.create`. Examples -------- <class 'MySimilarityFunction'> <class 'MyAnalogyFunction'> """


    if issubclass(class_, WordEmbeddingSimilarityFunction):
        register_ = registry.get_register_func(
            WordEmbeddingSimilarityFunction,
            'word embedding similarity evaluation function')
    elif issubclass(class_, WordEmbeddingAnalogyFunction):
        register_ = registry.get_register_func(
            WordEmbeddingAnalogyFunction,
            'word embedding analogy evaluation function')
    else:
        raise RuntimeError(
            'The custom function must either subclass '
            'WordEmbeddingSimilarityFunction or WordEmbeddingAnalogyFunction')

    return register_(class_)