diff --git a/pymatgen/analysis/diffusion/neb/full_path_mapper.py b/pymatgen/analysis/diffusion/neb/full_path_mapper.py
index 7c3cff0..c141085 100644
--- a/pymatgen/analysis/diffusion/neb/full_path_mapper.py
+++ b/pymatgen/analysis/diffusion/neb/full_path_mapper.py
@@ -159,7 +159,7 @@ def unique_hops(self):
         return {d["hop_label"]: d for u, v, d in ihop_data}
 
     @classmethod
-    def with_base_structure(cls, base_structure: Structure, m_graph: StructureGraph, **kwargs) -> "MigrationGraph":
+    def with_base_structure(cls, base_structure: Structure, m_graph: StructureGraph, **kwargs) -> MigrationGraph:
         """
         Args:
             base_structure: base framework structure that does not contain any
@@ -174,7 +174,7 @@ def with_base_structure(cls, base_structure: Structure, m_graph: StructureGraph,
     @classmethod
     def with_local_env_strategy(
         cls, structure: Structure, migrating_specie: str, nn: NearNeighbors, **kwargs
-    ) -> "MigrationGraph":
+    ) -> MigrationGraph:
         """
         Using a specific nn strategy to get the connectivity graph between all the migrating ion sites.
         Args:
@@ -191,7 +191,7 @@ def with_local_env_strategy(
     @classmethod
     def with_distance(
         cls, structure: Structure, migrating_specie: str, max_distance: float, **kwargs
-    ) -> "MigrationGraph":
+    ) -> MigrationGraph:
         """
         Using a specific nn strategy to get the connectivity graph between all the migrating ion sites.
         Args: