diff --git a/pkg/suggestion/v1alpha3/chocolate/base_chocolate_service.py b/pkg/suggestion/v1alpha3/chocolate/base_chocolate_service.py
index 8cb1b708412..9173f3aa8b5 100644
--- a/pkg/suggestion/v1alpha3/chocolate/base_chocolate_service.py
+++ b/pkg/suggestion/v1alpha3/chocolate/base_chocolate_service.py
@@ -1,11 +1,9 @@
-import json
-import numpy as np
 import chocolate as choco
 import logging
 import base64
 
-from pkg.suggestion.v1alpha3.internal.search_space import *
-from pkg.suggestion.v1alpha3.internal.trial import *
+from pkg.suggestion.v1alpha3.internal.constant import *
+from pkg.suggestion.v1alpha3.internal.trial import Assignment
 
 logger = logging.getLogger(__name__)
 
diff --git a/pkg/suggestion/v1alpha3/chocolate_service.py b/pkg/suggestion/v1alpha3/chocolate_service.py
index 1fa75a43528..db5341a55b3 100644
--- a/pkg/suggestion/v1alpha3/chocolate_service.py
+++ b/pkg/suggestion/v1alpha3/chocolate_service.py
@@ -3,9 +3,9 @@
 
 from pkg.apis.manager.v1alpha3.python import api_pb2
 from pkg.apis.manager.v1alpha3.python import api_pb2_grpc
-from pkg.apis.manager.health.python import health_pb2
 
-from pkg.suggestion.v1alpha3.internal.search_space import HyperParameter, HyperParameterSearchSpace, DOUBLE
+from pkg.suggestion.v1alpha3.internal.constant import *
+from pkg.suggestion.v1alpha3.internal.search_space import HyperParameterSearchSpace
 from pkg.suggestion.v1alpha3.internal.trial import Trial, Assignment
 from pkg.suggestion.v1alpha3.chocolate.base_chocolate_service import BaseChocolateService
 from pkg.suggestion.v1alpha3.base_health_service import HealthServicer
diff --git a/pkg/suggestion/v1alpha3/hyperopt/base_hyperopt_service.py b/pkg/suggestion/v1alpha3/hyperopt/base_hyperopt_service.py
index 3674823ba7e..f9a900fe535 100644
--- a/pkg/suggestion/v1alpha3/hyperopt/base_hyperopt_service.py
+++ b/pkg/suggestion/v1alpha3/hyperopt/base_hyperopt_service.py
@@ -2,14 +2,15 @@
 import numpy as np
 import logging
 
-from pkg.suggestion.v1alpha3.internal.search_space import *
-from pkg.suggestion.v1alpha3.internal.trial import *
+from pkg.suggestion.v1alpha3.internal.constant import *
+from pkg.suggestion.v1alpha3.internal.trial import Assignment
 
 logger = logging.getLogger(__name__)
 
 TPE_ALGORITHM_NAME = "tpe"
 RANDOM_ALGORITHM_NAME = "random"
 
+
 class BaseHyperoptService(object):
     def __init__(self, algorithm_name=TPE_ALGORITHM_NAME, random_state=None, search_space=None):
         self.algorithm_name = algorithm_name
@@ -64,7 +65,6 @@ def create_fmin(self):
 
         self.fmin.catch_eval_exceptions = False
 
-
     def getSuggestions(self, trials, request_number):
         """
         Get the new suggested trials with the given algorithm.
diff --git a/pkg/suggestion/v1alpha3/internal/__init__.py b/pkg/suggestion/v1alpha3/internal/__init__.py
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/pkg/suggestion/v1alpha3/internal/constant.py b/pkg/suggestion/v1alpha3/internal/constant.py
new file mode 100644
index 00000000000..e0b9715e938
--- /dev/null
+++ b/pkg/suggestion/v1alpha3/internal/constant.py
@@ -0,0 +1,7 @@
+MAX_GOAL = "MAXIMIZE"
+MIN_GOAL = "MINIMIZE"
+
+INTEGER = "INTEGER"
+DOUBLE = "DOUBLE"
+CATEGORICAL = "CATEGORICAL"
+DISCRETE = "DISCRETE"
diff --git a/pkg/suggestion/v1alpha3/internal/search_space.py b/pkg/suggestion/v1alpha3/internal/search_space.py
index fcc0dcf3375..379685fead9 100644
--- a/pkg/suggestion/v1alpha3/internal/search_space.py
+++ b/pkg/suggestion/v1alpha3/internal/search_space.py
@@ -1,13 +1,8 @@
 import logging
 from pkg.apis.manager.v1alpha3.python import api_pb2 as api
 
-MAX_GOAL = "MAXIMIZE"
-MIN_GOAL = "MINIMIZE"
+from .constant import *
 
-INTEGER = "INTEGER"
-DOUBLE = "DOUBLE"
-CATEGORICAL = "CATEGORICAL"
-DISCRETE = "DISCRETE"
 
 logging.basicConfig(level=logging.DEBUG)
 logger = logging.getLogger(__name__)
diff --git a/pkg/suggestion/v1alpha3/skopt/base_skopt_service.py b/pkg/suggestion/v1alpha3/skopt/base_skopt_service.py
index 4cb91cb1e6a..8ef5a4ece8c 100644
--- a/pkg/suggestion/v1alpha3/skopt/base_skopt_service.py
+++ b/pkg/suggestion/v1alpha3/skopt/base_skopt_service.py
@@ -1,11 +1,9 @@
-import json
-import numpy as np
-import skopt
+import datetime
 import logging
+import skopt
 
-from pkg.suggestion.v1alpha3.internal.search_space import *
-from pkg.suggestion.v1alpha3.internal.trial import *
-import datetime
+from pkg.suggestion.v1alpha3.internal.constant import *
+from pkg.suggestion.v1alpha3.internal.trial import Assignment
 
 logger = logging.getLogger(__name__)
 
diff --git a/pkg/suggestion/v1alpha3/skopt_service.py b/pkg/suggestion/v1alpha3/skopt_service.py
index 9c7dbd2f171..9f05b0d3a7c 100644
--- a/pkg/suggestion/v1alpha3/skopt_service.py
+++ b/pkg/suggestion/v1alpha3/skopt_service.py
@@ -2,7 +2,7 @@
 
 from pkg.apis.manager.v1alpha3.python import api_pb2
 from pkg.apis.manager.v1alpha3.python import api_pb2_grpc
-from pkg.suggestion.v1alpha3.internal.search_space import HyperParameter, HyperParameterSearchSpace
+from pkg.suggestion.v1alpha3.internal.search_space import HyperParameterSearchSpace
 from pkg.suggestion.v1alpha3.internal.trial import Trial, Assignment
 from pkg.suggestion.v1alpha3.skopt.base_skopt_service import BaseSkoptService
 from pkg.suggestion.v1alpha3.base_health_service import HealthServicer