replace or operator with Union to be Python 3.8 compatible

.snippets/14.md

@@ -8,3 +8,4 @@ affected: all
 - to be compatible as speficied in `pyproject.toml` classifier list
 - add Python matrix to test workflow with Python versions `['3.8', '3.9', '3.10', '3.11']`
 - use `actions/checkout` with version `v4`
+- use Python 3.8 compatible typing, replace `|` with `Union`

snippets2changelog/cli.py

@@ -9,7 +9,7 @@
 from argparse import Namespace as Args
 from pathlib import Path
 from sys import stdout
-from typing import Sequence
+from typing import Sequence, Union
 
 from .common import LOG_LEVELS, collect_user_choice
 from .creator import ChangelogCreator, SnippetCreator
@@ -32,7 +32,7 @@ def does_exist(parser: ArgumentParser, arg: str) -> Path:
         return Path(arg)
 
 
-def parse_args(argv: Sequence[str] | None = None) -> Args:
+def parse_args(argv: Union[Sequence[str], None] = None) -> Args:
     """Multi command argument parser"""
     parser = ArgumentParser(__doc__)
     parser.add_argument(

snippets2changelog/common.py

@@ -4,7 +4,7 @@
 import json
 import logging
 from pathlib import Path
-from typing import Any, Dict, List
+from typing import Any, Dict, List, Union
 
 import yaml
 
@@ -27,7 +27,7 @@ def collect_user_choice(question: str, options: List[str]) -> str:
             print(f"Invalid input: '{choice}', choose from: {options}")
 
 
-def read_file(path: Path, parse: str = "read", mode: str = "r") -> Dict[Any, Any] | str | List[str] | Any:
+def read_file(path: Path, parse: str = "read", mode: str = "r") -> Union[Dict[Any, Any], str, List[str], Any]:
     with open(path, mode) as file:
         if parse == "read":
             return file.read()
@@ -46,7 +46,7 @@ def read_file(path: Path, parse: str = "read", mode: str = "r") -> Dict[Any, Any
             )
 
 
-def save_file(content: str | Dict[Any, Any], path: Path, mode: str = "w", render: str = "txt") -> None:
+def save_file(content: Union[str, Dict[Any, Any]], path: Path, mode: str = "w", render: str = "txt") -> None:
     """
     Save a file to the specified path with the given content.
 

snippets2changelog/parser.py

@@ -20,7 +20,7 @@ class SnippetParserError(Exception):
 class SnippetParser(object):
     """docstring for SnippetCreator"""
 
-    def __init__(self, additional_keys: tuple[str] | tuple[()] = (), verbosity: int = 0) -> None:
+    def __init__(self, additional_keys: Union[tuple[str], tuple[()]] = (), verbosity: int = 0) -> None:
         self._file_name = Path()
         self._required_parser_keys = ("type", "scope", "affected") + additional_keys
         self._parsed_content = dict(zip(self._required_parser_keys, [""] * len(self._required_parser_keys)))