diff --git a/Xlib/ext/nvcontrol.py b/Xlib/ext/nvcontrol.py
index 7a21826..637c720 100644
--- a/Xlib/ext/nvcontrol.py
+++ b/Xlib/ext/nvcontrol.py
@@ -302,7 +302,7 @@ def get_cooler_manual_control_enabled(self, target):
 
 
 def set_cooler_manual_control_enabled(self, target, enabled):
-    return set_int_attribute(self, target, 0, NV_CTRL_GPU_COOLER_MANUAL_CONTROL, 1 if enabled else 0) == 1
+    return set_int_attribute(self, target, 0, NV_CTRL_GPU_COOLER_MANUAL_CONTROL, 1 if enabled else 0)
 
 
 def get_fan_duty(self, target):
diff --git a/Xlib/protocol/display.py b/Xlib/protocol/display.py
index 0d910da..ee5bef0 100644
--- a/Xlib/protocol/display.py
+++ b/Xlib/protocol/display.py
@@ -326,13 +326,13 @@ def get_extension_major(self, extname):
         return self.extension_major_opcodes[extname]
 
     def add_extension_event(self, code, evt, subcode=None):
-       if subcode == None:
-           self.event_classes[code] = evt
-       else:
-           if not code in self.event_classes:
-               self.event_classes[code] = {subcode: evt}
-           else:
-               self.event_classes[code][subcode] = evt
+        if subcode is None:
+            self.event_classes[code] = evt
+        else:
+            if not code in self.event_classes:
+                self.event_classes[code] = {subcode: evt}
+            else:
+                self.event_classes[code][subcode] = evt
 
     def add_extension_error(self, code, err):
         self.error_classes[code] = err
@@ -820,11 +820,11 @@ def parse_event_response(self, etype):
             length = 32
 
         estruct = self.event_classes.get(etype, event.AnyEvent)
-        if type(estruct) == dict:
+        if isinstance(estruct, dict):
             subcode = self.data_recv[1]
 
             # Python2 compatibility
-            if type(subcode) == str:
+            if isinstance(subcode, str):
                 subcode = ord(subcode)
 
             # this etype refers to a set of sub-events with individual subcodes
diff --git a/Xlib/protocol/rq.py b/Xlib/protocol/rq.py
index 8bc8205..1b6c491 100644
--- a/Xlib/protocol/rq.py
+++ b/Xlib/protocol/rq.py
@@ -295,10 +295,7 @@ def __init__(self, name, codes = (), default = None):
         self.codes = codes
 
     def check_value(self, value):
-        if hasattr(value, self.cast_function):
-            return getattr(value, self.cast_function)()
-        else:
-            return value
+        return getattr(value, self.cast_function, lambda: value)()
 
     def parse_value(self, value, display):
         # if not display:
@@ -860,7 +857,7 @@ def parse_binary_value(self, data, display, length, format):
         from . import event
 
         estruct = display.event_classes.get(byte2int(data) & 0x7f, event.AnyEvent)
-        if type(estruct) == dict:
+        if isinstance(estruct, dict):
             # this etype refers to a set of sub-events with individual subcodes
             estruct = estruct[indexbytes(data, 1)]
 
@@ -1078,7 +1075,7 @@ def pack_value(self, value):
 
         """
 
-        if type(value) is tuple:
+        if isinstance(value, tuple):
             return self.to_binary(*value)
         elif isinstance(value, dict):
             return self.to_binary(**value)
@@ -1220,7 +1217,7 @@ def pack_value(self, value):
 
         for v in value:
             # Let values be simple strings, meaning a delta of 0
-            if type(v) in (str, bytes):
+            if isinstance(v, (str, bytes)):
                 v = (0, v)
 
             # A tuple, it should be (delta, string)
diff --git a/Xlib/rdb.py b/Xlib/rdb.py
index 03b06e2..93d4cdd 100644
--- a/Xlib/rdb.py
+++ b/Xlib/rdb.py
@@ -70,7 +70,7 @@ def insert_file(self, file):
 
         """
 
-        if type(file) is bytes:
+        if isinstance(file, bytes):
             file = open(file, 'r')
 
         self.insert_string(file.read())
@@ -382,7 +382,7 @@ class _Match(object):
     def __init__(self, path, dbs):
         self.path = path
 
-        if type(dbs) is tuple:
+        if isinstance(dbs, tuple):
             self.skip = 0
             self.group = dbs