def METHOD_NAME():
    x = np.array([1, 2, 3, 6], dtype="float64")
    df = vaex.from_arrays(x=x)
    hashmap = df._hash_map_unique("x")._internal
    start = sys.getrefcount(hashmap)
    binner = vaex.superagg.BinnerHash_float64("x", hashmap)
    start_binner = sys.getrefcount(binner)
    assert sys.getrefcount(hashmap) == start + 1
    binner_copy = binner.copy()
    assert sys.getrefcount(hashmap) == start_binner + 1
    assert sys.getrefcount(hashmap) == start + 2
    binner.set_data(x)