diff --git a/api/advent22_api/core/advent_image.py b/api/advent22_api/core/advent_image.py
index 813165d..f170f52 100644
--- a/api/advent22_api/core/advent_image.py
+++ b/api/advent22_api/core/advent_image.py
@@ -1,7 +1,7 @@
 import colorsys
 import logging
 from dataclasses import dataclass
-from typing import AnyStr, Self, TypeAlias
+from typing import Self, cast
 
 import numpy as np
 from PIL import Image as PILImage
@@ -11,9 +11,9 @@ from PIL.ImageFont import FreeTypeFont
 
 from .config import Config
 
-_RGB: TypeAlias = tuple[int, int, int]
-_XY: TypeAlias = tuple[float, float]
-_Box: TypeAlias = tuple[int, int, int, int]
+type _RGB = tuple[int, int, int]
+type _XY = tuple[float, float]
+type _Box = tuple[int, int, int, int]
 
 _logger = logging.getLogger(__name__)
 
@@ -56,7 +56,7 @@ class AdventImage:
     async def get_text_box(
         self,
         xy: _XY,
-        text: AnyStr,
+        text: str,
         font: FreeTypeFont,
         anchor: str | None = "mm",
         **text_kwargs,
@@ -95,12 +95,12 @@ class AdventImage:
         pixel_data = np.asarray(self.img.crop(box))
         mean_color: np.ndarray = np.mean(pixel_data, axis=(0, 1))
 
-        return _RGB(mean_color.astype(int))
+        return cast(_RGB, mean_color.astype(int))
 
     async def hide_text(
         self,
         xy: _XY,
-        text: AnyStr,
+        text: str,
         font: FreeTypeFont,
         anchor: str | None = "mm",
         **text_kwargs,
@@ -134,8 +134,10 @@ class AdventImage:
         else:
             tc_v -= 3
 
-        text_color = colorsys.hsv_to_rgb(tc_h, tc_s, tc_v)
-        text_color = _RGB(int(val) for val in text_color)
+        text_color: tuple[int | float, int | float, int | float] = colorsys.hsv_to_rgb(
+            tc_h, tc_s, tc_v
+        )
+        text_color = cast(_RGB, tuple(int(val) for val in text_color))
 
         # Buchstaben verstecken
         ImageDraw.Draw(self.img).text(
diff --git a/api/advent22_api/core/calendar_config.py b/api/advent22_api/core/calendar_config.py
index 6760f09..8745232 100644
--- a/api/advent22_api/core/calendar_config.py
+++ b/api/advent22_api/core/calendar_config.py
@@ -1,5 +1,4 @@
 import tomllib
-from typing import TypeAlias
 
 import tomli_w
 from fastapi import Depends
@@ -20,7 +19,7 @@ class DoorSaved(BaseModel):
     y2: int
 
 
-DoorsSaved: TypeAlias = list[DoorSaved]
+type DoorsSaved = list[DoorSaved]
 
 
 class CalendarConfig(BaseModel):
diff --git a/api/advent22_api/core/settings.py b/api/advent22_api/core/settings.py
index d0d2408..73a27f2 100644
--- a/api/advent22_api/core/settings.py
+++ b/api/advent22_api/core/settings.py
@@ -1,10 +1,6 @@
-from typing import TypeVar
-
 from pydantic import BaseModel
 from pydantic_settings import BaseSettings, SettingsConfigDict
 
-T = TypeVar("T")
-
 
 class Credentials(BaseModel):
     username: str = ""
@@ -71,7 +67,7 @@ class Settings(BaseSettings):
     # openapi settings
     #####
 
-    def __dev_value(self, value: T) -> T | None:
+    def __dev_value[T](self, value: T) -> T | None:
         if self.production_mode:
             return None