diff --git a/libgunshotmatch/consolidate/__init__.py b/libgunshotmatch/consolidate/__init__.py
index 6cf0aa8..a683281 100644
--- a/libgunshotmatch/consolidate/__init__.py
+++ b/libgunshotmatch/consolidate/__init__.py
@@ -41,6 +41,7 @@
 from pyms.DPA.Alignment import Alignment
 from pyms.Spectrum import MassSpectrum
 from pyms_nist_search import ReferenceData, SearchResult
+from typing_extensions import Self
 
 # this package
 from libgunshotmatch.consolidate._fields import (
@@ -715,7 +716,7 @@ class ConsolidatedPeakFilter:
 	verbose: bool = False
 
 	@classmethod
-	def from_method(cls: Type["ConsolidatedPeakFilter"], method: ConsolidateMethod) -> "ConsolidatedPeakFilter":
+	def from_method(cls: Type[Self], method: ConsolidateMethod) -> Self:
 		"""
 		Construct a :class:`~.ConsolidatedPeakFilter` from a :class:`~.ConsolidateMethod`.
 
diff --git a/requirements.txt b/requirements.txt
index 409a3c6..2597607 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -11,3 +11,4 @@ scipy>=1.9.0
 sdjson>=0.4.0
 tomli>=1.2.3; python_version < "3.11"
 tomli-w>=1.0.0
+typing-extensions>=4.12.2