remove unused lib

pip_review/__main__.py

@@ -1,18 +1,15 @@
 from __future__ import absolute_import
-import os
 import re
 import argparse
 from functools import partial
 import logging
 import json
 import sys
 import pip
-import subprocess
 from packaging import version
 
 PY3 = sys.version_info.major == 3
 if PY3:  # Python3 Imports
-    import urllib.request as urllib_request
     import subprocess
 
     def check_output(*args, **kwargs):

setup.py

@@ -1,7 +1,6 @@
 """
 pip-review lets you smoothly manage all available PyPI updates.
 """
-import sys
 from setuptools import setup