[#3287] fix pylint warnings

- C0115: Missing class docstring (missing-class-docstring)
- C0123: Use isinstance() rather than type() for a typecheck. (unidiomatic-typecheck)
- C0201: Consider iterating the dictionary directly instead of calling .keys() (consider-iterating-dictionary)
- C0206: Consider iterating with .items() (consider-using-dict-items)
- C0411: standard import "..." should be placed before "..." (wrong-import-order)
- C0415: Import outside toplevel (...) (import-outside-toplevel)
- C1802: Do not use `len(SEQUENCE)` without comparison to determine if a sequence is empty (use-implicit-booleaness-not-len)
- E0001: Parsing failed: 'invalid syntax (<unknown>, line 2313)' (syntax-error)
- E0401: Unable to import '...' (import-error)
- E0602: Undefined variable 'l' (undefined-variable)
- R0205: Class 'VagrantEnv' inherits from object, can be safely removed from bases in python3 (useless-object-inheritance)
- E1101: Instance of 'NSECBASE' has no 'dump_fixedpart' member (no-member)
- E1123: Unexpected keyword argument 'capture' in method call (unexpected-keyword-arg)
- R0902: Too many instance attributes (too-many-instance-attributes)
- R0913: Too many arguments (too-many-arguments)
- R0916: Too many boolean expressions in if statement (6/5) (too-many-boolean-expressions)
- R1717: Consider using a dictionary comprehension (consider-using-dict-comprehension)
- R1722: Consider using 'sys.exit' instead (consider-using-sys-exit)
- R1732: Consider using 'with' for resource-allocating operations (consider-using-with)
- R1735: Consider using '{}' instead of a call to 'dict'. (use-dict-literal)
- W0102: Dangerous default value sys.argv[1:] (builtins.list) as argument (dangerous-default-value)
- W0102: Dangerous default value {} as argument (dangerous-default-value)
- W0106: Expression "[f.write('%02x' % x) for x in bin_address]" is assigned to nothing (expression-not-assigned)
- W0107: Unnecessary pass statement (unnecessary-pass)
- W0201: Attribute 'config' defined outside __init__ (attribute-defined-outside-init)
- W0404: Reimport '...' (imported line ...) (reimported)
- W0611: Unused import ... (unused-import)
- W0612: Unused variable '...' (unused-variable)
- W0613: Unused argument '...' (unused-argument)
- W0621: Redefining name '...' from outer scope (line 1471) (redefined-outer-name)
- W0622: Redefining built-in '...' (redefined-builtin)
- W0707: Consider explicitly re-raising using 'raise ... from ...' (raise-missing-from)
- W0718: Catching too general exception Exception (broad-exception-caught)
- W1202: Use lazy % formatting in logging functions (logging-format-interpolation)
- W1203: Use lazy % formatting in logging functions (logging-fstring-interpolation)
- W1308: Duplicate string formatting argument 'connection_type', consider passing as named argument (duplicate-string-formatting-argument)
- W1401: Anomalous backslash in string: '\/'. String constant might be missing an r prefix. (anomalous-backslash-in-string)
- W1406: The u prefix for strings is no longer necessary in Python >=3.0 (redundant-u-string-prefix)
- W1514: Using open without explicitly specifying an encoding (unspecified-encoding)
- W4901: Deprecated module 'optparse' (deprecated-module)
- W4904: Using deprecated class SafeConfigParser of module configparser (deprecated-class)

3 files changed, 39 insertions, 47 deletions

diff --git a/tools/git-obsolete-branch.py b/tools/git-obsolete-branch.py
index 2639b21a7d..d1485aa1cb 100755
--- a/tools/git-obsolete-branch.py
+++ b/tools/git-obsolete-branch.py
@@ -15,7 +15,7 @@
 # git pull
 # git remote prune origin
 #
-# This script requires python 2.7 or 3.
+# This script requires python 3.
 #
 # I have limited experience in Python. If things are done in a strange or
 # uncommon way, there are no obscure reasons to do it that way, just plain
@@ -23,9 +23,7 @@
 #
 #                                                                        tomek
 
-import string
-import sys
-from optparse import OptionParser
+import argparse
 
 # [B404:blacklist] Consider possible security implications associated with subprocess module.
 import subprocess  # nosec B404
@@ -157,39 +155,31 @@ def check_output(cmd):
     return subprocess.check_output(cmd)  # nosec B603
 
 
-def parse_args(args=sys.argv[1:], Parser=OptionParser):
-
-    parser = Parser(description="This script prints out merged and/or unmerged"
-                    " branches of a GIT tree.")
-
-    parser.add_option("-c", "--csv", action="store_true",
-                      default=False, help="generates CSV output")
-    parser.add_option("-u", "--unmerged", action="store_true",
-                      default=False, help="lists unmerged branches")
-    parser.add_option("-m", "--skip-merged", action="store_true",
-                      default=False, help="omits listing merged branches")
-    parser.add_option("-s", "--stats", action="store_true",
-                      default=False, help="prints also statistics")
-
-    (options, args) = parser.parse_args(args)
+def parse_args():
+    parser = argparse.ArgumentParser(
+        description="This script prints out merged and/or unmerged branches of a GIT tree.",
+        usage="""%prog
+    Lists all obsolete (fully merged into master) branches.
+""")
 
-    if args:
-        parser.print_help()
-        sys.exit(1)
+    parser.add_argument("-c", "--csv", action="store_true",
+                        default=False, help="generates CSV output")
+    parser.add_argument("-u", "--unmerged", action="store_true",
+                        default=False, help="lists unmerged branches")
+    parser.add_argument("-m", "--skip-merged", action="store_true",
+                        default=False, help="omits listing merged branches")
+    parser.add_argument("-s", "--stats", action="store_true",
+                        default=False, help="prints also statistics")
 
-    return options
+    return parser.parse_args()
 
 
 def main():
-    usage = """%prog
-    Lists all obsolete (fully merged into master) branches.
-    """
-
-    options = parse_args()
-    csv = options.csv
-    merged = not options.skip_merged
-    unmerged = options.unmerged
-    stats = options.stats
+    args = parse_args()
+    csv = args.csv
+    merged = not args.skip_merged
+    unmerged = args.unmerged
+    stats = args.stats
 
     if csv:
         print("branch name,status,date,last commit(mail),last commit(name)")
diff --git a/tools/kea-breeder/kb.py b/tools/kea-breeder/kb.py
index 3122b0f720..4ee8d5c5d2 100755
--- a/tools/kea-breeder/kb.py
+++ b/tools/kea-breeder/kb.py
@@ -1,14 +1,14 @@
 #!/usr/bin/env python3
 
 import argparse
-from termcolor import colored, cprint
-from io import StringIO
 import json
 import os
 import re
-import sqlalchemy as db
-from sqlalchemy.sql import select
 import sys
+from io import StringIO
+
+import sqlalchemy as db  # pylint: disable=import-error
+from termcolor import cprint  # pylint: disable=import-error
 
 
 def convert_to_db(entity_name, make_singular=True):
@@ -86,6 +86,7 @@ class State:
 
 class ConfigFile:
     def __init__(self, filename):
+        self.config = {}
         self.filename = filename
 
     def load(self):
@@ -93,7 +94,7 @@ class ConfigFile:
             print('The all keys file %s does not exist.' % self.filename)
             sys.exit(1)
 
-        with open(self.filename) as f:
+        with open(self.filename, encoding='utf-8') as f:
             self.config = json.load(f)
             f.close()
 
@@ -232,17 +233,17 @@ def main():
         sys.exit(1)
 
     sanitized_contents = ''
-    f = open(args.all_keys_file)
-    for line in f:
-        sanitized_line = line.strip()
-        if not sanitized_line:
-            continue
+    with open(args.all_keys_file, encoding='utf-8') as f:
+        for line in f:
+            sanitized_line = line.strip()
+            if not sanitized_line:
+                continue
 
-        if sanitized_line.find('//') != -1 or sanitized_line.find('#') != -1:
-            continue
+            if sanitized_line.find('//') != -1 or sanitized_line.find('#') != -1:
+                continue
 
-        sanitized_line = sanitized_line.replace(': .', ': 0.')
-        sanitized_contents = sanitized_contents + sanitized_line
+            sanitized_line = sanitized_line.replace(': .', ': 0.')
+            sanitized_contents = sanitized_contents + sanitized_line
 
     f.close()
 
diff --git a/tools/reorder_message_file.py b/tools/reorder_message_file.py
index 9483a58d96..368282dd13 100644
--- a/tools/reorder_message_file.py
+++ b/tools/reorder_message_file.py
@@ -160,7 +160,8 @@ def process_file(filename):
     Parameters:
     filename     Name of the message file to process
     """
-    lines = open(filename).read().splitlines()
+    with open(filename, encoding='utf-8') as f:
+        lines = f.read().splitlines()
 
     # Search for the first line starting with the percent character.  Everything
     # before it is considered the file header and is copied to the output with