Fix LGTM alerts

Author: Jostar Yang

platform/broadcom/sonic-platform-modules-accton/as5835-54x/sonic_platform/watchdog.py

@@ -7,8 +7,6 @@
 #############################################################################
 
 try:
-    import os
-    import sys
     from sonic_platform_pddf_base.pddf_watchdog import PddfWatchdog
 except ImportError as e:
     raise ImportError(str(e) + "- required module not found")

platform/broadcom/sonic-platform-modules-accton/as5835-54x/utils/accton_as5835_54x_pddf_monitor.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright (C) 2019 Accton Technology Corporation
 #
@@ -23,16 +23,10 @@
 # ------------------------------------------------------------------
 
 try:
-    import os
     import sys, getopt
-    import subprocess
-    import click
-    import imp
     import logging
     import logging.config
-    import types
-    import time  # this is only being used as part of the example
-    import traceback
+    import time
     import signal
     from tabulate import tabulate
     from sonic_platform import platform
@@ -44,8 +38,6 @@
 FUNCTION_NAME = 'accton_as5835_54x_monitor'
 DUTY_MAX = 100
 
-global log_file
-global log_level
 platform_chassis = None
 
 test_temp = 0
@@ -88,7 +80,6 @@ def manage_fans(self):
 
         THERMAL_NUM_MAX=4
         FAN_LEV1_UP_TEMP = 57700  # temperature
-        FAN_LEV1_DOWN_TEMP = 0    # unused
         FAN_LEV1_SPEED_PERC = DUTY_MAX # percentage*/
 
         FAN_LEV2_UP_TEMP = 53000
@@ -99,27 +90,22 @@ def manage_fans(self):
         FAN_LEV3_DOWN_TEMP = 47700
         FAN_LEV3_SPEED_PERC = 65
 
-        FAN_LEV4_UP_TEMP = 0     # unused
         FAN_LEV4_DOWN_TEMP = 42700
         FAN_LEV4_SPEED_PERC = 40
 
         FAN_NUM=2
         FAN_TRAY_NUM=5
-        
-        #thermal = ThermalUtil()
-        #fan = FanUtil()
+
         if test_temp_revert==0:
             temp_test_data=temp_test_data+2000
         else:            
             temp_test_data=temp_test_data-2000
 
         if test_temp==0:
-            #temp2 = thermal.get_thermal_2_val()
             temp2=platform_chassis.get_thermal(1).get_temperature()*1000
             if temp2 is None:
                 return False
 
-            #temp3 = thermal.get_thermal_3_val()
             temp3=platform_chassis.get_thermal(2).get_temperature()*1000
             if temp3 is None:
                 return False

platform/broadcom/sonic-platform-modules-accton/as5835-54x/utils/pddf_switch_svc.py

@@ -1,8 +1,6 @@
 #!/usr/bin/env python
 # Script to stop and start the respective platforms default services. 
 # This will be used while switching the pddf->non-pddf mode and vice versa
-import os
-import sys
 import commands
 
 def check_pddf_support():