Groom test_network_util.

* Visually separate right from wrong testcases.
* Add provision for running test without nosetest support.
* Remove execute flag.

test/test_network_util.py

@@ -1,23 +1,26 @@
 import unittest
 
-import network_util
+from node import network_util
 
 
 class TestNodeNetworkUtil(unittest.TestCase):
     def test_is_loopback_addr(self):
         self.assertTrue(network_util.is_loopback_addr("127.0.0.1"))
         self.assertTrue(network_util.is_loopback_addr("localhost"))
+
         self.assertFalse(network_util.is_loopback_addr("10.0.0.1"))
         self.assertFalse(network_util.is_loopback_addr("192.168.0.1"))
 
     def test_is_valid_port(self):
         self.assertTrue(network_util.is_valid_port(1))
         self.assertTrue(network_util.is_valid_port(65335))
+
         self.assertFalse(network_util.is_valid_port(-1))
         self.assertFalse(network_util.is_valid_port(70000))
 
     def test_is_valid_protocol(self):
         self.assertTrue(network_util.is_valid_protocol('tcp'))
+
         self.assertFalse(network_util.is_valid_protocol('udp'))
         self.assertFalse(network_util.is_valid_protocol('baz'))
 
@@ -27,16 +30,22 @@ def test_is_private_ip_address(self):
         self.assertTrue(network_util.is_private_ip_address('192.168.1.1'))
         self.assertTrue(network_util.is_private_ip_address('172.16.1.1'))
         self.assertTrue(network_util.is_private_ip_address('10.1.1.1'))
+
         self.assertFalse(network_util.is_private_ip_address('8.8.8.8'))
 
     def test_uri_parts(self):
         self.assertEqual(
             ('tcp', 'localhost', '1234'),
             network_util.uri_parts('tcp://localhost:1234')
         )
+
         self.assertEqual(
             ('tcp', '1.1.1.1', '22'),
             network_util.uri_parts('tcp://1.1.1.1:22')
         )
+
         with self.assertRaises(RuntimeError):
             network_util.uri_parts('tcp://::1234')
+
+if __name__ == '__main__':
+    unittest.main()