diff --git a/data_structures/hashing/hash_table_with_linked_list.py b/data_structures/hashing/hash_table_with_linked_list.py
index f404c5251246..c8dffa30b8e8 100644
--- a/data_structures/hashing/hash_table_with_linked_list.py
+++ b/data_structures/hashing/hash_table_with_linked_list.py
@@ -8,7 +8,7 @@ def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
 
     def _set_value(self, key, data):
-        self.values[key] = deque([]) if self.values[key] is None else self.values[key]
+        self.values[key] = deque() if self.values[key] is None else self.values[key]
         self.values[key].appendleft(data)
         self._keys[key] = self.values[key]
 
diff --git a/machine_learning/linear_discriminant_analysis.py b/machine_learning/linear_discriminant_analysis.py
index 8528ccbbae51..af5248c4dbc4 100644
--- a/machine_learning/linear_discriminant_analysis.py
+++ b/machine_learning/linear_discriminant_analysis.py
@@ -252,7 +252,7 @@ def accuracy(actual_y: list, predicted_y: list) -> float:
 num = TypeVar("num")
 
 
-def valid_input(
+def valid_input[num](
     input_type: Callable[[object], num],  # Usually float or int
     input_msg: str,
     err_msg: str,
diff --git a/maths/volume.py b/maths/volume.py
index 1715c9c300d5..f48d388b423e 100644
--- a/maths/volume.py
+++ b/maths/volume.py
@@ -510,6 +510,32 @@ def vol_torus(torus_radius: float, tube_radius: float) -> float:
     return 2 * pow(pi, 2) * torus_radius * pow(tube_radius, 2)
 
 
+def vol_octahedron(oct_side: float) -> float:
+    """
+    | Calculate the Volume of an Octahedron.
+    | Wikipedia reference: https://en.wikipedia.org/wiki/Regular_octahedron
+
+    >>> from math import isclose
+    >>> isclose(vol_octahedron(2.5), 7.36569563735987)
+    True
+    >>> isclose(vol_octahedron(10), 471.40452079103168)
+    True
+    >>> isclose(vol_octahedron(5), 58.92556509887896)
+    True
+    >>> isclose(vol_octahedron(3.5), 20.21146882891548)
+    True
+    >>> vol_octahedron(0)
+    0.0
+    >>> vol_octahedron(-1)
+    Traceback (most recent call last):
+        ...
+    ValueError: vol_octahedron() only accepts non-negative values
+    """
+    if oct_side < 0:
+        raise ValueError("vol_octahedron() only accepts non-negative values")
+    return oct_side**3 * 2**0.5 / 3
+
+
 def vol_icosahedron(tri_side: float) -> float:
     """
     | Calculate the Volume of an Icosahedron.
@@ -560,6 +586,7 @@ def main():
     print(
         f"Hollow Circular Cylinder: {vol_hollow_circular_cylinder(1, 2, 3) = }"
     )  # ~= 28.3
+    print(f"Octahedron: {vol_octahedron(2.5) = }")  # ~=7.37
     print(f"Icosahedron: {vol_icosahedron(2.5) = }")  # ~=34.09
 
 
diff --git a/searches/jump_search.py b/searches/jump_search.py
index e72d85e8a868..b443d09283b0 100644
--- a/searches/jump_search.py
+++ b/searches/jump_search.py
@@ -20,7 +20,7 @@ def __lt__(self, other: Any, /) -> bool: ...
 T = TypeVar("T", bound=Comparable)
 
 
-def jump_search(arr: Sequence[T], item: T) -> int:
+def jump_search[T: Comparable](arr: Sequence[T], item: T) -> int:
     """
     Python implementation of the jump search algorithm.
     Return the index if the `item` is found, otherwise return -1.