Translate python2 to python3

*opencas.py*: changed result class to contain text values instead of bytes,
translated chache configuring methods to py3,
*init script*: changed regex input on raw string to work in py3.

Signed-off-by: Slawomir_Jankowski <slawomir.jankowski@intel.com>

utils/casctl

@@ -1,10 +1,9 @@
-#!/usr/bin/env python2
+#!/usr/bin/env python3
 #
 # Copyright(c) 2012-2019 Intel Corporation
 # SPDX-License-Identifier: BSD-3-Clause-Clear
 #
 
-from __future__ import print_function
 import argparse
 import sys
 import re
@@ -42,7 +41,7 @@ def add_core_recursive(core, config):
             .format(core.device, core.cache_id))
         exit(3)
     core.marked = True
-    match = re.match('/dev/cas(\d)-(\d).*', core.device)
+    match = re.match(r'/dev/cas(\d)-(\d).*', core.device)
     if match:
         cache_id,core_id = match.groups()
         with_error = add_core_recursive(config.caches[int(cache_id)].cores[int(core_id)], config)

utils/open-cas-loader

@@ -1,10 +1,9 @@
-#!/usr/bin/env python2
+#!/usr/bin/env python3
 #
 # Copyright(c) 2012-2019 Intel Corporation
 # SPDX-License-Identifier: BSD-3-Clause-Clear
 #
 
-from __future__ import print_function
 import subprocess
 import time
 import opencas

utils/opencas.py

@@ -17,11 +17,11 @@ class casadm:
 
     class result:
         def __init__(self, cmd):
-            p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-            self.exit_code = p.wait()
-            output = p.communicate()
-            self.stdout = output[0]
-            self.stderr = output[1]
+            p = subprocess.run(cmd, universal_newlines=True, stdout=subprocess.PIPE,
+                               stderr=subprocess.PIPE)
+            self.exit_code = p.returncode
+            self.stdout = p.stdout
+            self.stderr = p.stderr
 
     class CasadmError(Exception):
         def __init__(self, result):
@@ -500,10 +500,10 @@ def start_cache(cache, load, force=False):
             force=force)
 
 def configure_cache(cache):
-    if cache.params.has_key('cleaning_policy'):
+    if 'cleaning_policy' in cache.params:
         casadm.set_param('cleaning', cache_id=cache.cache_id,
                 policy=cache.params['cleaning_policy'])
-    if cache.params.has_key('ioclass_file'):
+    if 'ioclass_file' in cache.params:
         casadm.io_class_load_config(cache_id=cache.cache_id,
                 ioclass_file=cache.params['ioclass_file'])