diff --git a/pyproject.toml b/pyproject.toml
index 41e13faa..d3424366 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -79,13 +79,11 @@ exclude = [
 ]
 
 line-length = 130
-
 target-version = "py310"
+show-fixes = true
 
 [tool.ruff.lint]
-# Enable Pyflakes (`F`) and a subset of the pycodestyle (`E`) codes by default.
-# Unlike Flake8, Ruff doesn't enable pycodestyle warnings (`W`) or
-select = ["E4", "E7", "E9", "F", "I", "UP"]
+select = ["E4", "E7", "E9", "F", "I", "UP", "TCH"]
 ignore = []
 
 # Allow fix for all enabled rules (when `--fix`) is provided.
diff --git a/theHarvester/lib/core.py b/theHarvester/lib/core.py
index 9a4915fc..84a656d9 100644
--- a/theHarvester/lib/core.py
+++ b/theHarvester/lib/core.py
@@ -4,9 +4,8 @@
 import contextlib
 import random
 import ssl
-from collections.abc import Sized
 from pathlib import Path
-from typing import Any
+from typing import TYPE_CHECKING, Any
 
 import aiohttp
 import certifi
@@ -17,6 +16,9 @@
 
 from .version import version
 
+if TYPE_CHECKING:
+    from collections.abc import Sized
+
 DATA_DIR = Path(__file__).parents[1] / 'data'
 CONFIG_DIRS = [
     Path('/etc/theHarvester/'),