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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 ngrams(path, elem, ignore_hash=True):
 """ Yields N-grams from a JSTOR DfR dataset. Parameters path : string Path to unzipped JSTOR DfR folder containing N-grams. elem : string Name of subdirectory containing N-grams. (e.g. 'bigrams'). ignore_hash : bool If True, will exclude all N-grams that contain the hash '#' character. Returns ------- ngrams : :class:`.FeatureSet` """


    grams = GramGenerator(path, elem, ignore_hash=ignore_hash)
    return FeatureSet({k: Feature(f) for k, f in grams})