How to use the cfgrib.bindings.codes_get_array function in cfgrib

def test_codes_get_array_errors():
    grib = bindings.codes_grib_new_from_file(open(TEST_DATA))

    with pytest.raises(bindings.GribInternalError) as err:
        bindings.codes_get_array(grib, 'values', size=1)  # too short
    assert err.value.code == bindings.lib.GRIB_ARRAY_TOO_SMALL

    with pytest.raises(bindings.GribInternalError) as err:
        bindings.codes_get_array(grib, 'values', key_type=int)  # wrong type
    assert err.value.code == bindings.lib.GRIB_NOT_IMPLEMENTED

def test_codes_get_array(key, expected_value):
    grib = bindings.codes_grib_new_from_file(open(TEST_DATA))

    result = bindings.codes_get_array(grib, key)

    assert result == expected_value

def test_codes_get_array_errors():
    grib = bindings.codes_grib_new_from_file(open(TEST_DATA))

    with pytest.raises(bindings.GribInternalError) as err:
        bindings.codes_get_array(grib, 'values', size=1)  # too short
    assert err.value.code == bindings.lib.GRIB_ARRAY_TOO_SMALL

    with pytest.raises(bindings.GribInternalError) as err:
        bindings.codes_get_array(grib, 'values', key_type=int)  # wrong type
    assert err.value.code == bindings.lib.GRIB_NOT_IMPLEMENTED

def message_get(self, item, key_type=None, default=_MARKER):
        # type: (str, type, T.Any) -> T.Any
        """Get value of a given key as its native or specified type."""
        try:
            values = eccodes.codes_get_array(self.codes_id, item, key_type)
            if values is None:
                values = ['unsupported_key_type']
        except eccodes.KeyValueNotFoundError:
            if default is _MARKER:
                raise KeyError(item)
            else:
                return default
        if len(values) == 1:
            if isinstance(values, np.ndarray):
                values = values.tolist()
            return values[0]
        return values