diff --git a/src/ptulsconv/pdf/__init__.py b/src/ptulsconv/pdf/__init__.py
index 49d6fa6..df9bb92 100644
--- a/src/ptulsconv/pdf/__init__.py
+++ b/src/ptulsconv/pdf/__init__.py
@@ -284,15 +284,10 @@ class GRect:
         return self.inset_xy(d, d)
 
     def __repr__(self):
-        return "<GRect x=%f y=%f width=%f height=%f>" % (
-            self.x,
-            self.y,
-            self.width,
-            self.height,
-        )
+        return f"<GRect x={self.x} y={self.y} width={self.width} height={self.height}>"
 
     def divide_x(self, x_list, direction="l"):
-        ret_list = list()
+        ret_list = []
 
         rem = self
         for item in x_list:
@@ -302,7 +297,7 @@ class GRect:
         return ret_list, rem
 
     def divide_y(self, y_list, direction="u"):
-        ret_list = list()
+        ret_list = []
 
         rem = self
         for item in y_list:
diff --git a/src/ptulsconv/reporting.py b/src/ptulsconv/reporting.py
index 8fc3b70..7ea7b9c 100644
--- a/src/ptulsconv/reporting.py
+++ b/src/ptulsconv/reporting.py
@@ -9,30 +9,30 @@ import sys
 
 def print_banner_style(message):
     if sys.stderr.isatty():
-        sys.stderr.write("\n\033[1m%s\033[0m\n\n" % message)
+        sys.stderr.write(f"\n\033[1m{message}\033[0m\n\n")
     else:
-        sys.stderr.write("\n%s\n\n" % message)
+        sys.stderr.write(f"\n{message}\n\n")
 
 
 def print_section_header_style(message):
     if sys.stderr.isatty():
-        sys.stderr.write("\n\033[4m%s\033[0m\n\n" % message)
+        sys.stderr.write(f"\n\033[4m{message}\033[0m\n\n")
     else:
-        sys.stderr.write("%s\n\n" % message)
+        sys.stderr.write(f"{message}\n\n")
 
 
 def print_status_style(message):
     if sys.stderr.isatty():
-        sys.stderr.write("\033[3m - %s\033[0m\n" % message)
+        sys.stderr.write(f"\033[3m - {message}\033[0m\n")
     else:
-        sys.stderr.write(" - %s\n" % message)
+        sys.stderr.write(f" - {message}\n")
 
 
 def print_warning(warning_string):
     if sys.stderr.isatty():
-        sys.stderr.write("\033[3m - %s\033[0m\n" % warning_string)
+        sys.stderr.write(f"\033[3m - {warning_string}\033[0m\n")
     else:
-        sys.stderr.write(" - %s\n" % warning_string)
+        sys.stderr.write(f" - {warning_string}\n")
 
 
 def print_advisory_tagging_error(
@@ -44,30 +44,30 @@ def print_advisory_tagging_error(
         ok_string = failed_string[:position]
         not_ok_string = failed_string[position:]
         sys.stderr.write(
-            '\033[32m"%s\033[31;1m%s"\033[0m\n' % (ok_string, not_ok_string)
+            f'\033[32m"{ok_string}\033[31;1m{not_ok_string}"\033[0m\n'
         )
 
         if parent_track_name is not None:
-            sys.stderr.write(' !   > On track "%s"\n' % parent_track_name)
+            sys.stderr.write(f' !   > On track "{parent_track_name}"\n')
 
         if clip_time is not None:
-            sys.stderr.write(" !   > In clip name at %s\n" % clip_time)
+            sys.stderr.write(f" !   > In clip name at {clip_time}\n")
     else:
         sys.stderr.write("\n")
-        sys.stderr.write(' ! Tagging error: "%s"\n' % failed_string)
+        sys.stderr.write(f' ! Tagging error: "{failed_string}"\n')
         sys.stderr.write(" ! %s _______________⬆\n" % (" " * position))
 
         if parent_track_name is not None:
-            sys.stderr.write(' !   > On track "%s"\n' % parent_track_name)
+            sys.stderr.write(f' !   > On track "{parent_track_name}"\n')
 
         if clip_time is not None:
-            sys.stderr.write(" !   > In clip name at %s\n" % clip_time)
+            sys.stderr.write(f" !   > In clip name at {clip_time}\n")
 
     sys.stderr.write("\n")
 
 
 def print_fatal_error(message):
     if sys.stderr.isatty():
-        sys.stderr.write("\n\033[5;31;1m*** %s ***\033[0m\n" % message)
+        sys.stderr.write(f"\n\033[5;31;1m*** {message} ***\033[0m\n")
     else:
-        sys.stderr.write("\n%s\n" % message)
+        sys.stderr.write(f"\n{message}\n")
diff --git a/src/ptulsconv/validations.py b/src/ptulsconv/validations.py
index 8b525a8..e7890f1 100644
--- a/src/ptulsconv/validations.py
+++ b/src/ptulsconv/validations.py
@@ -2,9 +2,10 @@
 Validation logic for enforcing various consistency rules.
 """
 
+from __future__ import annotations
+
 from collections.abc import Iterator
 from dataclasses import dataclass
-from typing import Optional
 
 from ptulsconv.docparser.adr_entity import ADRLine
 
@@ -12,7 +13,7 @@ from ptulsconv.docparser.adr_entity import ADRLine
 @dataclass
 class ValidationError:
     message: str
-    event: Optional[ADRLine] = None
+    event: ADRLine | None = None
 
     def report_message(self):
         if self.event is not None:
@@ -25,7 +26,7 @@ class ValidationError:
 
 
 def validate_unique_count(input_lines: Iterator[ADRLine], field="title", count=1):
-    values = set(list(map(lambda e: getattr(e, field), input_lines)))
+    values = {getattr(e, field) for e in input_lines}
     if len(values) > count:
         yield ValidationError(
             message=f"Field {field} has too many values (max={count}): {values}"
@@ -36,15 +37,13 @@ def validate_value(input_lines: Iterator[ADRLine], key_field, predicate):
     for event in input_lines:
         val = getattr(event, key_field)
         if not predicate(val):
-            yield ValidationError(
-                message=f"Field {val} not in range", event=event
-            )
+            yield ValidationError(message=f"Field {val} not in range", event=event)
 
 
 def validate_unique_field(
     input_lines: Iterator[ADRLine], field="cue_number", scope=None
 ):
-    values = dict()
+    values = {}
     for event in input_lines:
         this = getattr(event, field)
         if scope is not None:
@@ -72,7 +71,7 @@ def validate_dependent_value(
     Validates that two events with the same value in `key_field` always have
     the same value in `dependent_field`
     """
-    key_values = set(getattr(x, key_field) for x in input_lines)
+    key_values = {getattr(x, key_field) for x in input_lines}
 
     for key_value in key_values:
         rows = [