diff --git a/zulip_botserver/tests/server_test_lib.py b/zulip_botserver/tests/server_test_lib.py
index 18364c5..70ecaff 100644
--- a/zulip_botserver/tests/server_test_lib.py
+++ b/zulip_botserver/tests/server_test_lib.py
@@ -1,14 +1,15 @@
-from unittest import TestCase
-import zulip_botserver.server
 import json
-from typing import Any, List, Dict, Mapping, Optional
+
+from typing import Any, List, Dict, Optional
+from unittest import TestCase
+from zulip_botserver import server
 
 class BotServerTestCase(TestCase):
 
     def setUp(self):
         # type: () -> None
-        zulip_botserver.server.app.testing = True
-        self.app = zulip_botserver.server.app.test_client()
+        server.app.testing = True
+        self.app = server.app.test_client()
 
     def assert_bot_server_response(self,
                                    available_bots=None,
@@ -21,14 +22,14 @@ class BotServerTestCase(TestCase):
                                    ):
         # type: (Optional[List[str]], Optional[Dict[str, Any]], Optional[Dict[str, Any]], Optional[Dict[str, Any]], str, Dict[str, Dict[str, Any]], bool) -> None
         if available_bots is not None:
-            zulip_botserver.server.available_bots = available_bots
-            zulip_botserver.server.bots_config = bots_config  # type: ignore # monkey-patching
-            zulip_botserver.server.load_lib_modules()
-            zulip_botserver.server.load_bot_handlers()
+            server.available_bots = available_bots
+            server.bots_config = bots_config  # type: ignore # monkey-patching
+            server.load_lib_modules()
+            server.load_bot_handlers()
 
         response = self.app.post(payload_url, data=json.dumps(message))
 
         if check_success:
-            assert response.status_code >= 200 and response.status_code < 300
+            assert 200 <= response.status_code < 300
         else:
-            assert response.status_code >= 400 and response.status_code < 500
+            assert 400 <= response.status_code < 500
diff --git a/zulip_botserver/tests/test_server.py b/zulip_botserver/tests/test_server.py
index b870679..a295ff6 100644
--- a/zulip_botserver/tests/test_server.py
+++ b/zulip_botserver/tests/test_server.py
@@ -2,7 +2,6 @@ from __future__ import absolute_import
 import mock
 import unittest
 from typing import Any
-from zulip_botserver import server
 from .server_test_lib import BotServerTestCase
 import six
 
diff --git a/zulip_botserver/zulip_botserver/server.py b/zulip_botserver/zulip_botserver/server.py
index 45d6680..cab082c 100644
--- a/zulip_botserver/zulip_botserver/server.py
+++ b/zulip_botserver/zulip_botserver/server.py
@@ -1,13 +1,11 @@
-from __future__ import absolute_import
-from __future__ import print_function
-
 import os
 import sys
 import json
 import argparse
+
 from flask import Flask, request
 from importlib import import_module
-from typing import Any, Dict, Mapping, Union, List, Tuple
+from typing import Any, Dict, Mapping, Union, List
 from werkzeug.exceptions import BadRequest
 from six.moves.configparser import SafeConfigParser
 
@@ -122,19 +120,17 @@ def parse_args():
     parser = argparse.ArgumentParser(usage=usage)
     parser.add_argument('--config-file',
                         action='store',
-                        help='(config file for the zulip bot server (flaskbotrc))')
+                        required=True,
+                        help='Config file for the zulip bot server (flaskbotrc)')
     parser.add_argument('--hostname',
                         action='store',
                         default="127.0.0.1",
-                        help='(address on which you want to run the server)')
+                        help='Address on which you want to run the server')
     parser.add_argument('--port',
                         action='store',
                         default=5002,
-                        help='(port on which you want to run the server)')
-    options = parser.parse_args()
-    if not options.config_file:  # if flaskbotrc is not given
-        parser.error('Flaskbotrc not given')
-    return options
+                        help='Port on which you want to run the server')
+    return parser.parse_args()
 
 
 def main():