diff --git a/crawlab/requirements.txt b/crawlab/requirements.txt
index 11af6f69..8b13446c 100644
--- a/crawlab/requirements.txt
+++ b/crawlab/requirements.txt
@@ -1,7 +1,6 @@
 aiohttp==3.5.4
 amqp==2.4.2
 aniso8601==6.0.0
-Appium-Python-Client==0.40
 APScheduler==3.6.0
 asn1crypto==0.24.0
 async-timeout==3.0.1
@@ -59,7 +58,6 @@ pytz==2018.9
 queuelib==1.5.0
 redis==3.2.1
 redisbeat==1.1.4
-reppy==0.4.12
 requests==2.21.0
 Scrapy==1.6.0
 selenium==3.141.0
diff --git a/crawlab/routes/tasks.py b/crawlab/routes/tasks.py
index e531e81d..5ae7648b 100644
--- a/crawlab/routes/tasks.py
+++ b/crawlab/routes/tasks.py
@@ -1,8 +1,11 @@
 import json
 import os
 import sys
-from _signal import SIGINT, SIGKILL
-from datetime import datetime
+
+try:
+    from _signal import SIGKILL
+except ImportError:
+    pass
 
 import requests
 from bson import ObjectId
@@ -13,7 +16,6 @@ from db.manager import db_manager
 from routes.base import BaseApi
 from utils import jsonify
 from utils.spider import get_spider_col_fields
-from utils.log import other
 
 
 class TaskApi(BaseApi):