def METHOD_NAME():
    """Fetch associations between neuropeptides and their receptors from Bentley data.
    :return: dict from neuropeptide gene names (upper case) to cognate receptor gene names (upper case).
    """
    url = BASE_URL + "neuropeptide_receptor_mapping.tsv"
    mapping = defaultdict(set)
    for row in csv.DictReader(decode_lines(urlopen(url)), delimiter='\t'):
        if int(row.get("excluded", 0)):
            continue
        mapping[row["neuropeptide"].upper()].add(row["receptor"].upper())
    return mapping