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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 from_mmap(cls, fname):
 """ Create a WordVectors class from a memory map Parameters fname : path to file Returns ------- WordVectors instance """

        memmaped = joblib.load(fname, mmap_mode="r+")
        return cls(vocab=memmaped.vocab, vectors=memmaped.vectors)