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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 load_default_model_sentencizer(lang):
 """ Load a generic spaCy model and add the sentencizer for sentence tokenization"""

    loading_start = time.time()
    lang_class = get_lang_class(lang)
    nlp = lang_class()
    nlp.add_pipe(nlp.create_pipe('sentencizer'))
    loading_end = time.time()
    loading_time = loading_end - loading_start
    return nlp, loading_time, lang + "_default_" + 'sentencizer'