style: some of the suggestions from flake8
diff --git a/serial/urlhandler/protocol_alt.py b/serial/urlhandler/protocol_alt.py
index 6c81813..af1646a 100644
--- a/serial/urlhandler/protocol_alt.py
+++ b/serial/urlhandler/protocol_alt.py
@@ -16,9 +16,6 @@
 #   use poll based implementation on Posix (Linux):
 #   python -m serial.tools.miniterm alt:///dev/ttyUSB0?class=PosixPollSerial
 
-import sys
-import time
-
 import serial
 
 try:
@@ -50,5 +47,5 @@
 
 # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 if __name__ == '__main__':
-    s = serial_for_url('alt:///dev/ttyS0?class=PosixPollSerial')
+    s = serial.serial_for_url('alt:///dev/ttyS0?class=PosixPollSerial')
     print(s)