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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 save_ldamodel_to_pickle(picklefile, model, vocab, doc_labels, dtm=None, **kwargs):
 """Save a LDA model as pickle file."""

    pickle_data({'model': model, 'vocab': vocab, 'doc_labels': doc_labels, 'dtm': dtm}, picklefile)