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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 read_vest_pickle(gname, score_dir):
 """Read in VEST scores for given gene. Parameters gname : str name of gene score_dir : str directory containing vest scores Returns ------- gene_vest : dict or None dict containing vest scores for gene. Returns None if not found. """

    vest_path = os.path.join(score_dir, gname+".vest.pickle")
    if os.path.exists(vest_path):
        if sys.version_info < (3,):
            with open(vest_path) as handle:
                gene_vest = pickle.load(handle)
        else:
            with open(vest_path, 'rb') as handle:
                gene_vest = pickle.load(handle, encoding='latin-1')
        return gene_vest
    else:
        return None