further fixes of py3 issues

complaints by pylint are mainly related to
- remove object from base list in class definitions
- unnecessary else/elif after return/raise

Change-Id: I13d15449149cc8bba0562338d0c9c42e97163bdf
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/21325
Tested-by: JenkinsCodeReview <bjoern_pedersen@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>

secop/lib/__init__.py

@@ -32,6 +32,7 @@ import subprocess
 import sys
 import threading
 import traceback
+import importlib
 from os import path
 
 repodir = path.abspath(path.join(path.dirname(__file__), '..', '..'))
@@ -51,7 +52,7 @@ CONFIG = {
 
 unset_value = object()
 
-class lazy_property(object):
+class lazy_property:
     """A property that calculates its value only once."""
 
     def __init__(self, func):
@@ -89,7 +90,6 @@ def clamp(_min, value, _max):
 def get_class(spec):
     """loads a class given by string in dotted notaion (as python would do)"""
     modname, classname = spec.rsplit('.', 1)
-    import importlib
     if modname.startswith('secop'):
         module = importlib.import_module(modname)
     else:

secop/lib/enum.py

@@ -26,7 +26,7 @@
 __ALL__ = ['Enum']
 
 
-class EnumMember(object):
+class EnumMember:
     """represents one member of an Enum
 
     has an int-type value and attributes 'name' and 'value'
@@ -53,7 +53,7 @@ class EnumMember(object):
             return -1  # XXX:!
         if self.value < other:
             return -1
-        elif self.value > other:
+        if self.value > other:
             return 1
         return 0
 
@@ -262,7 +262,7 @@ class Enum(dict):
         elif isinstance(parent, dict):
             for k, v in parent.items():
                 add(self, k, v)
-        elif parent != None:
+        elif parent is not None:
             raise TypeError('parent (if given) MUST be a dict or an Enum!')
         for k, v in kwds.items():
             add(self, k, v)
@@ -286,7 +286,7 @@ class Enum(dict):
         raise TypeError('Enum %r can not be changed!' % self.name)
 
     def __repr__(self):
-        return '<Enum %r (%d values)>' % (self.name, len(self)/2)
+        return '<Enum %r (%d values)>' % (self.name, len(self)//2)
 
     def __call__(self, key):
         return self[key]

secop/lib/parsing.py

@@ -149,7 +149,7 @@ def format_args(args):
     return repr(args)  # for floats/ints/...
 
 
-class ArgsParser(object):
+class ArgsParser:
     """returns a pythonic object from the input expression
 
     grammar:
@@ -164,10 +164,8 @@ class ArgsParser(object):
     name = [A-Za-z_] [A-Za-z0-9_]*
     """
 
-    DIGITS_CHARS = [c for c in '0123456789']
-    NAME_CHARS = [
-        c for c in '_ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'
-    ]
+    DIGITS_CHARS = '0123456789'
+    NAME_CHARS = '_ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'
     NAME_CHARS2 = NAME_CHARS + DIGITS_CHARS
 
     def __init__(self, string=''):
@@ -276,7 +274,7 @@ class ArgsParser(object):
 
     def parse_record(self):
         """record_expr = '(' (name '=' expr ',')* ')' """
-        if self.get != '(':
+        if self.get() != '(':
             return None
         self.skip()
         res = {}

secop/lib/sequence.py

@@ -30,11 +30,11 @@ from secop.errors import IsBusyError
 from secop.lib import mkthread
 
 
-class Namespace(object):
+class Namespace:
     pass
 
 
-class Step(object):
+class Step:
 
     def __init__(self, desc, waittime, func, *args, **kwds):
         self.desc = desc
@@ -44,7 +44,7 @@ class Step(object):
         self.kwds = kwds
 
 
-class SequencerMixin(object):
+class SequencerMixin:
     """Mixin for worker classes that need to execute a sequence of actions,
     including waits, that exceeds the usual Tango timeout (about 3 seconds)
     and should be executed asynchronously.
@@ -129,11 +129,11 @@ class SequencerMixin(object):
     def read_status(self):
         if self.seq_is_alive():
             return self.Status.BUSY, 'moving: ' + self._seq_phase
-        elif self._seq_error:
+        if self._seq_error:
             if self._seq_fault_on_error:
                 return self.Status.ERROR, self._seq_error
             return self.Status.WARN, self._seq_error
-        elif self._seq_stopped:
+        if self._seq_stopped:
             if self._seq_fault_on_stop:
                 return self.Status.ERROR, self._seq_stopped
             return self.Status.WARN, self._seq_stopped