fix: Update function signature to support multiple arguments

Author: caffeine-addictt

src/thread/_types.py

@@ -5,7 +5,7 @@
 """
 
 from typing import Any, Literal, Callable, Union
-from typing_extensions import ParamSpec, TypeVar
+from typing_extensions import ParamSpec, TypeVar, Concatenate
 
 
 # Descriptive Types
@@ -34,4 +34,4 @@
 HookFunction = Callable[[_Target_T], Union[Any, None]]
 
 _Dataset_T = TypeVar('_Dataset_T')
-DatasetFunction = Callable[[_Dataset_T], _Target_T]
+DatasetFunction = Callable[Concatenate[_Dataset_T, _Target_P], _Target_T]

src/thread/thread.py

@@ -346,7 +346,7 @@ class ParallelProcessing(Generic[_Target_P, _Target_T, _Dataset_T]):
 
   def __init__(
     self,
-    function: DatasetFunction[_Dataset_T, _Target_T],
+    function: DatasetFunction[_Dataset_T, _Target_P, _Target_T],
     dataset: Sequence[_Dataset_T],
     max_threads: int = 8,
     *overflow_args: Overflow_In,