diff --git a/ydb/apps/dstool/lib/arg_parser.py b/ydb/apps/dstool/lib/arg_parser.py
index e924feb98fde..163deb553cfc 100644
--- a/ydb/apps/dstool/lib/arg_parser.py
+++ b/ydb/apps/dstool/lib/arg_parser.py
@@ -97,7 +97,7 @@ def _additional_eq(self, other):
 
     def __eq__(self, other):
         return all((
-            type(self) == type(other),
+            type(self) is type(other),
             self.name == other.name,
             self.type == other.type,
             self.choices == other.choices,
diff --git a/ydb/apps/dstool/lib/common.py b/ydb/apps/dstool/lib/common.py
index 36ac04d360b2..9835bf869c97 100644
--- a/ydb/apps/dstool/lib/common.py
+++ b/ydb/apps/dstool/lib/common.py
@@ -818,20 +818,23 @@ def fetch_json_info(entity, nodes=None, enums=1):
     elif entity == 'vdiskinfo':
         section, keycols = 'VDiskStateInfo', ['NodeId', 'PDiskId', 'VDiskSlotId']
 
-        def merge(x, y):
+        def merge_fn(x, y):
             return max([x, y], key=lambda x: x.get('GroupGeneration', 0))
+        merge = merge_fn
     elif entity == 'tabletinfo':
         section, keycols = 'TabletStateInfo', ['TabletId']
 
-        def merge(x, y):
+        def merge_fn(x, y):
             return max([x, y], key=lambda x: x.get('Generation', 0))
+        merge = merge_fn
     elif entity == 'bsgroupinfo':
         section, keycols = 'BSGroupStateInfo', ['GroupID']
 
-        def merge(x, y):
+        def merge_fn(x, y):
             return x if x.get('GroupGeneration', 0) > y.get('GroupGeneration', 0) else \
                 y if y.get('GroupGeneration', 0) > x.get('GroupGeneration', 0) else \
                 x if x.get('VDiskIds', []) else y
+        merge = merge_fn
     else:
         assert False
     res = {}
diff --git a/ydb/library/yql/core/expr_nodes_gen/gen/__main__.py b/ydb/library/yql/core/expr_nodes_gen/gen/__main__.py
index 2bc809f4e7e0..b381e64b5d0e 100755
--- a/ydb/library/yql/core/expr_nodes_gen/gen/__main__.py
+++ b/ydb/library/yql/core/expr_nodes_gen/gen/__main__.py
@@ -1,6 +1,5 @@
 import os
 import sys
-import getopt
 import json
 import re
 
@@ -17,7 +16,7 @@
 env = Environment(loader=FileSystemLoader(templateDir))
 template = env.get_template(templateFilename)
 
-json_data=open(jsonFile)
+json_data = open(jsonFile)
 model = json.load(json_data)
 json_data.close()
 
@@ -51,7 +50,7 @@
                 child["Optional"] = False
 
     if node["Base"] == model["FreeArgCallableBase"]:
-        aux["isFinal"] = True;
+        aux["isFinal"] = True
 
 # Traverse tree
 nodesMap = {}
@@ -135,7 +134,7 @@ def isListBuilder(node):
             raise Exception("Child #" + str(index) + " should be optional in " + node["Name"])
         optionalArgs = child["Optional"]
         if not child["Optional"]:
-            aux["fixedChildrenCount"] += 1;
+            aux["fixedChildrenCount"] += 1
 
     if "Match" in node and node["Match"]["Type"] == "CallableBase":
         namesToMatch = aux["namesToMatch"] = []
@@ -202,4 +201,3 @@ def addUsages(typename):
 defsOutput = template.render(generator=__file__, genType="Definitions", model=model, nodes=model["Nodes"])
 with open(defsOutFile, "w") as fh:
     fh.write(defsOutput)
-