diff --git a/pymatgen/core/structure.py b/pymatgen/core/structure.py
index 54ba5d5a657..6a04ae24628 100644
--- a/pymatgen/core/structure.py
+++ b/pymatgen/core/structure.py
@@ -18,7 +18,7 @@
 import warnings
 from abc import ABCMeta, abstractmethod
 from fnmatch import fnmatch
-from typing import Any, Dict, Iterable, Iterator, List, Optional, Sequence, Set, Tuple, Union, Callable, Literal
+from typing import Any, Callable, Dict, Iterable, Iterator, List, Literal, Optional, Sequence, Set, Tuple, Union
 
 import numpy as np
 from monty.dev import deprecated
@@ -2358,19 +2358,20 @@ def from_str(
         Returns:
             IStructure / Structure
         """
-        from pymatgen.io.atat import Mcsqs
-        from pymatgen.io.cif import CifParser
-        from pymatgen.io.cssr import Cssr
-        from pymatgen.io.vasp import Poscar
-        from pymatgen.io.xcrysden import XSF
 
         fmt_low = fmt.lower()
         if fmt_low == "cif":
+            from pymatgen.io.cif import CifParser
+
             parser = CifParser.from_string(input_string)
             s = parser.get_structures(primitive=primitive)[0]
         elif fmt_low == "poscar":
+            from pymatgen.io.vasp import Poscar
+
             s = Poscar.from_string(input_string, False, read_velocities=False).structure
         elif fmt_low == "cssr":
+            from pymatgen.io.cssr import Cssr
+
             cssr = Cssr.from_string(input_string)
             s = cssr.structure
         elif fmt_low == "json":
@@ -2380,8 +2381,12 @@ def from_str(
             d = yaml.safe_load(input_string)
             s = Structure.from_dict(d)
         elif fmt_low == "xsf":
+            from pymatgen.io.xcrysden import XSF
+
             s = XSF.from_string(input_string).structure
         elif fmt_low == "mcsqs":
+            from pymatgen.io.atat import Mcsqs
+
             s = Mcsqs.structure_from_string(input_string)
         else:
             raise ValueError(f"Unrecognized format `{fmt}`!")