Use current version for release notes generation

RELEASE.rst

@@ -6,8 +6,7 @@ How to release a new version of Python Holidays
   - switch to ``beta`` branch and pull the most recent changes
     from https://github.com/vacanza/python-holidays remote ``beta`` branch.
   - generate release notes by running the following script
-    ``scripts/generate_release_notes.py -t <version>``, where <version> is the
-    value of tag/version you're going to release, e.g. 0.39
+    ``scripts/generate_release_notes.py``
   - insert the script's output into the top of ``CHANGES`` file
     (see previous release notes for consistent formatting)
   - commit the updated ``CHANGES`` file to ``beta`` branch with the following

scripts/generate_release_notes.py

@@ -14,8 +14,8 @@
 # flake8: noqa: T201
 
 import argparse
-import os
 import re
+import sys
 from datetime import date
 from pathlib import Path
 from typing import Dict, Set
@@ -24,6 +24,9 @@
 from github import Github
 from github.GithubException import UnknownObjectException
 
+sys.path.append(f"{Path.cwd()}")
+import holidays
+
 BRANCH_NAME = "beta"
 HEADER_TEMPLATE = """
 Version {version}
@@ -39,7 +42,7 @@ class ReleaseNotesGenerator:
     """
     Generates release notes based on local git commits and GitHub PRs metadata.
 
-    Usage example: scripts/generate_release_notes.py -t 0.24
+    Usage example: scripts/generate_release_notes.py
     """
 
     def __init__(self) -> None:
@@ -69,13 +72,6 @@ def __init__(self) -> None:
             nargs="+",
             type=int,
         )
-        arg_parser.add_argument(
-            "-t",
-            "--tag",
-            help="New release tag",
-            required=True,
-            type=str,
-        )
         arg_parser.add_argument(
             "-v",
             "--verbose",
@@ -85,12 +81,14 @@ def __init__(self) -> None:
         )
         self.args = arg_parser.parse_args()
 
-        self.local_repo = Repo(os.getcwd())
+        self.local_repo = Repo(Path.cwd())
         self.remote_repo = Github(self.github_token).get_repo(REPOSITORY_NAME)
 
         self.previous_commits: Set[str] = set()
         self.pull_requests: Dict[int, str] = {}
 
+        self.tag = holidays.__version__
+
         try:
             latest_tag = self.remote_repo.get_tags()[0]
             self.latest_tag_name = latest_tag.name
@@ -146,7 +144,7 @@ def add_pull_request(self, pull_request):
 
         # Skip failed release attempt PRs, version upgrades.
         pr_title = pull_request.title
-        skip_titles = (f"v.{self.args.tag}", "Bump", "Revert")
+        skip_titles = (f"v.{self.tag}", "Bump", "Revert")
         for skip_title in skip_titles:
             if pr_title.startswith(skip_title):
                 return None
@@ -246,7 +244,7 @@ def print_release_notes(self):
                 HEADER_TEMPLATE.format(
                     day=today.day,
                     month=today.strftime("%B"),
-                    version=self.args.tag,
+                    version=self.tag,
                     year=today.year,
                 )
             )