diff --git a/scripts/generators/csv_generator.py b/scripts/generators/csv_generator.py
index 8f83469e09..838f4fc75a 100644
--- a/scripts/generators/csv_generator.py
+++ b/scripts/generators/csv_generator.py
@@ -1,33 +1,10 @@
-# Licensed to Elasticsearch B.V. under one or more contributor
-# license agreements. See the NOTICE file distributed with
-# this work for additional information regarding copyright
-# ownership. Elasticsearch B.V. licenses this file to you under
-# the Apache License, Version 2.0 (the "License"); you may
-# not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-# 	http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing,
-# software distributed under the License is distributed on an
-# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-# KIND, either express or implied.  See the License for the
-# specific language governing permissions and limitations
-# under the License.
-
 import _csv
 import csv
 import sys
-from typing import (
-    Dict,
-    List,
-)
-
+from typing import Dict, List
 from os.path import join
+from _types import Field
 from generator import ecs_helpers
-from _types import (
-    Field,
-)
 
 
 def generate(ecs_flat: Dict[str, Field], version: str, out_dir: str) -> None:
@@ -39,35 +16,29 @@ def generate(ecs_flat: Dict[str, Field], version: str, out_dir: str) -> None:
 def base_first(ecs_flat: Dict[str, Field]) -> List[Field]:
     base_list: List[Field] = []
     sorted_list: List[Field] = []
+
     for field_name in sorted(ecs_flat):
         if '.' in field_name:
             sorted_list.append(ecs_flat[field_name])
         else:
             base_list.append(ecs_flat[field_name])
+
     return base_list + sorted_list
 
 
 def save_csv(file: str, sorted_fields: List[Field], version: str) -> None:
-    open_mode: str = "wb"
-    if sys.version_info >= (3, 0):
-        open_mode: str = "w"
+    open_mode = "w"
 
     with open(file, open_mode) as csvfile:
-        schema_writer: _csv._writer = csv.writer(csvfile,
-                                                 delimiter=',',
-                                                 quoting=csv.QUOTE_MINIMAL,
-                                                 lineterminator='\n')
-
+        schema_writer = csv.writer(csvfile, delimiter=',', quoting=csv.QUOTE_MINIMAL, lineterminator='\n')
         schema_writer.writerow(["ECS_Version", "Indexed", "Field_Set", "Field",
                                 "Type", "Level", "Normalization", "Example", "Description"])
+
         for field in sorted_fields:
-            key_parts: List[str] = field['flat_name'].split('.')
-            if len(key_parts) == 1:
-                field_set: str = 'base'
-            else:
-                field_set: str = key_parts[0]
+            key_parts = field['flat_name'].split('.')
+            field_set = 'base' if len(key_parts) == 1 else key_parts[0]
+            indexed = str(field.get('index', True)).lower()
 
-            indexed: str = str(field.get('index', True)).lower()
             schema_writer.writerow([
                 version,
                 indexed,