diff --git a/src/service/convlab/policy/policy.py b/src/service/convlab/policy/policy.py
deleted file mode 100644
index 5ac85a8..0000000
--- a/src/service/convlab/policy/policy.py
+++ /dev/null
@@ -1,24 +0,0 @@
-"""Policy Interface"""
-from convlab.util.module import Module
-
-
-class Policy(Module):
-    """Policy module interface."""
-
-    def predict(self, state):
-        """Predict the next agent action given dialog state.
-
-        Args:
-            state (dict or list of list):
-                when the policy takes dialogue state as input, the type is dict.
-                else when the policy takes dialogue act as input, the type is list of list.
-        Returns:
-            action (list of list or str):
-                when the policy outputs dialogue act, the type is list of list.
-                else when the policy outputs utterance directly, the type is str.
-        """
-        return []
-
-    def update_memory(self, utterance_list, state_list, action_list, reward_list):
-        pass
-
diff --git a/src/service/convlab/util/module.py b/src/service/convlab/util/module.py
deleted file mode 100644
index 9d280ce..0000000
--- a/src/service/convlab/util/module.py
+++ /dev/null
@@ -1,25 +0,0 @@
-"""module interface."""
-from abc import ABC
-
-
-class Module(ABC):
-
-    def train(self, *args, **kwargs):
-        """Model training entry point"""
-        pass
-
-    def test(self, *args, **kwargs):
-        """Model testing entry point"""
-        pass
-
-    def from_cache(self, *args, **kwargs):
-        """restore internal state for multi-turn dialog"""
-        return None
-
-    def to_cache(self, *args, **kwargs):
-        """save internal state for multi-turn dialog"""
-        return None
-
-    def init_session(self):
-        """Init the class variables for a new session."""
-        pass
diff --git a/src/service/convlab/util/restaurant/dbquery.py b/src/service/convlab/util/restaurant/dbquery.py
deleted file mode 100644
index 735874d..0000000
--- a/src/service/convlab/util/restaurant/dbquery.py
+++ /dev/null
@@ -1,38 +0,0 @@
-"""
-"""
-import json
-import os
-import random
-from fuzzywuzzy import fuzz
-from itertools import chain
-from copy import deepcopy
-
-
-class Database(object):
-    def __init__(self):
-        super(Database, self).__init__()
-        # loading databases
-        domains = ['menu', 'pizza', 'drink', 'size']
-        self.dbs = {}
-        for domain in domains:
-            with open(os.path.join(os.path.dirname(
-                    os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))),
-                    'data/restaurant/db/{}_db.json'.format(domain))) as f:
-                self.dbs[domain] = json.load(f)
-
-    def query(self, domain):
-        """Returns the list of entities for a given domain
-        based on the annotation of the belief state"""
-        # query the db
-        if domain == 'pizza':
-            return [{'Name': random.choice(self.dbs[domain]['name'])}]
-        if domain == 'menu':
-            return deepcopy(self.dbs[domain])
-        if domain == 'drink':
-            return [{'Name': random.choice(self.dbs[domain]['name'])}]
-        if domain == 'size':
-            return [{'Size': random.choice(self.dbs[domain]['size'])}]
-
-
-if __name__ == '__main__':
-    db = Database()
\ No newline at end of file
diff --git a/src/service/dialog_policy.py b/src/service/dialog_policy.py
index cafa615..12eaacc 100644
--- a/src/service/dialog_policy.py
+++ b/src/service/dialog_policy.py
@@ -56,4 +56,6 @@ class SimpleRulePolicy(Policy):
                 if domain in ["pizza", "drink"]:
                     system_action[(domain, 'Recommend')].append(['Name', choice['name']])
                 if domain in ["size"]:
-                    system_action[(domain, 'Recommend')].append(['Size', choice['size']])
\ No newline at end of file
+                    system_action[(domain, 'Recommend')].append(['Size', choice['size']])
+
+dialogPolicy = SimpleRulePolicy()
\ No newline at end of file