Add type hinting stub file

src/pyperclip/__init__.pyi

@@ -0,0 +1,32 @@
+# Type signature stub file for pyperclip,
+#
+# Pyperclip is delibarately backwards compatable with
+# python 2.6, and so type annotation within the source
+# directly are not an option.
+
+from typing import Callable, Optional
+
+# All and only those functions listed in __all__ are given
+# type annotated signatures here.
+
+
+def copy(text: str) -> None: ...
+
+
+def paste() -> str: ...
+
+
+# timeout will typically be an int, but floats work.
+def waitForPaste(timeout: Optional[float] = None) -> str: ...
+
+
+def waitForNewPaste(timeout: Optional[float] = None) -> str: ...
+
+
+def set_clipboard(clipboard: str) -> None: ...
+
+
+def determine_clipboard() -> tuple[
+        Callable[[str], None],
+        Callable[[], str]
+    ]: ...

src/pyperclip/py.typed

@@ -0,0 +1,5 @@
+"""
+To maintain compatibility with Python versions that do
+not support type hinting, the type hints are provided in the
+PEPs 484 and 561 stub file src/__init__.pyi
+"""