How to use the eccodes.GribMessage function in eccodes

def test_missing_message_behaviour(self):
        """Key with MISSING value."""
        with GribFile(TESTGRIB) as grib_file:
            msg = GribMessage(grib_file)
            self.assertTrue(msg.missing("scaleFactorOfSecondFixedSurface"))
            msg["scaleFactorOfSecondFixedSurface"] = 5
            msg.set_missing("scaleFactorOfSecondFixedSurface")
            #with self.assertRaises(KeyError):

def test_read_past_last_message(self):
        """Trying to open message on exhausted GRIB file raises IOError."""
        with GribFile(TESTGRIB) as grib_file:
            for _ in range(len(grib_file)):
                GribMessage(grib_file)
            self.assertRaises(IOError, lambda: GribMessage(grib_file))

def test_value_setting(self):
        """Keys can be set properly."""
        with GribFile(TESTGRIB) as grib_file:
            msg = GribMessage(grib_file)
            msg["scaleFactorOfSecondFixedSurface"] = 5
            msg["values"] = [1, 2, 3]
            self.assertEqual( msg['scaleFactorOfSecondFixedSurface'], 5 )

def test_serialize(self):
        """Message can be serialized to file."""
        with GribFile(TESTGRIB) as grib_file:
            msg = GribMessage(grib_file)
            with open(TEST_OUTPUT, "w") as test:
                msg.write(test)
        os.unlink(TEST_OUTPUT)

def test_memory_management(self):
        """Messages in GribFile can be opened and closed properly."""
        with GribFile(TESTGRIB) as grib_file:
            self.assertEqual(len(grib_file), 5)
            for i in range(len(grib_file)):
                msg = GribMessage(grib_file)
                self.assertEqual(msg["shortName"], "msl")
                self.assertEqual(msg['count'], i+1)
            self.assertEqual(len(grib_file.open_messages), 5)
        self.assertEqual(len(grib_file.open_messages), 0)

def test_multi_value_setting(self):
        """Multiple keys/values can be set properly."""
        msg = GribMessage(sample='GRIB1')
        msg[ 'paramId', 'stepType', 'edition' ] = 49, 'avg', 2
        self.assertEqual( msg['shortName'], '10fg' )
        # Another test
        with GribFile(TESTGRIB) as grib_file:
            msg = GribMessage(grib_file)
            msg[ 'setLocalDefinition', 'localDefinitionNumber' ] = 1,25
            msg[ 'typeOfFirstFixedSurface', 'typeOfSecondFixedSurface' ] = 1, 8
            msg[ ('typeOfFirstFixedSurface','typeOfSecondFixedSurface') ] = (1, 8) #Also works
            self.assertEqual( msg['localDefinitionNumber'], 25 )
            self.assertEqual( msg['typeOfLevel'], 'entireAtmosphere' )

def test_multi_value_setting(self):
        """Multiple keys/values can be set properly."""
        msg = GribMessage(sample='GRIB1')
        msg['paramId', 'stepType', 'edition'] = 49, 'avg', 2
        self.assertEqual(msg['shortName'], '10fg')
        # Another test
        with GribFile(TESTGRIB) as grib_file:
            msg = GribMessage(grib_file)
            msg['setLocalDefinition', 'localDefinitionNumber'] = 1, 25
            msg['typeOfFirstFixedSurface', 'typeOfSecondFixedSurface'] = 1, 8
            msg[('typeOfFirstFixedSurface', 'typeOfSecondFixedSurface')] = (1, 8)  # Also works
            self.assertEqual(msg['localDefinitionNumber'], 25)
            self.assertEqual(msg['typeOfLevel'], 'entireAtmosphere')

def test_serialize(self):
        """Message can be serialized to file."""
        with GribFile(TESTGRIB) as grib_file:
            msg = GribMessage(grib_file)
            with open(TEST_OUTPUT, "w") as test:
                msg.write(test)
        os.unlink(TEST_OUTPUT)

def test_metadata(self):
        """Metadata is read correctly from GribMessage."""
        with GribFile(TESTGRIB) as grib_file:
            msg = GribMessage(grib_file)
            msg_keys = list(msg.keys())
            for key in KNOWN_GRIB_KEYS:
                assert key in msg_keys, "key '%s' not found" % key
            # Size of message in bytes
            self.assertEqual(msg.size(), 160219)
            self.assertEqual(len(list(msg.keys())), len(msg))

def test_multi_value_setting(self):
        """Multiple keys/values can be set properly."""
        msg = GribMessage(sample='GRIB1')
        msg['paramId', 'stepType', 'edition'] = 49, 'avg', 2
        self.assertEqual(msg['shortName'], '10fg')
        # Another test
        with GribFile(TESTGRIB) as grib_file:
            msg = GribMessage(grib_file)
            msg['setLocalDefinition', 'localDefinitionNumber'] = 1, 25
            msg['typeOfFirstFixedSurface', 'typeOfSecondFixedSurface'] = 1, 8
            msg[('typeOfFirstFixedSurface', 'typeOfSecondFixedSurface')] = (1, 8)  # Also works
            self.assertEqual(msg['localDefinitionNumber'], 25)
            self.assertEqual(msg['typeOfLevel'], 'entireAtmosphere')