Downgrade to Python 3.8

.circleci/config.yml

@@ -3,7 +3,7 @@ version: 2.1
 jobs:
   build_and_test:
     docker:
-      - image: python:3.10-bullseye
+      - image: python:3.8-bullseye
 
     steps:
       - checkout
@@ -20,7 +20,7 @@ jobs:
       - run:
           name: Install poetry
           command: |
-            pip --verbose install poetry==1.3.2
+            pip --verbose install poetry==1.6.1
 
       - run:
           name: Install dependencies

.github/workflows/build.yaml

@@ -0,0 +1,51 @@
+name: Build, lint and test
+run-name: Build, lint and test triggered by ${{ github.actor }}
+
+on:
+  pull_request:
+  push:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        python-version: ["3.8", "3.9", "3.10", "3.11"]
+
+    steps:
+      - name: Print information
+        run: |
+          echo "The job was automatically triggered by a ${{ github.event_name }} event."
+          echo "This job is now running on a ${{ runner.os }} server hosted by GitHub!"
+          echo "The name of your branch is ${{ github.ref }} and your repository is ${{ github.repository }}."
+
+      - name: Check out repository code
+        uses: actions/checkout@v3
+
+      - name: Print more information
+        run: |
+          echo "The ${{ github.repository }} repository has been cloned to the runner."
+          echo "The workflow is now ready to test your code on the runner."
+
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v4
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Print Python version
+        run: |
+          python --version
+
+      - name: Install dependencies
+        run: |
+          pip install --upgrade pip
+          pip --verbose install poetry==1.6.1
+          poetry config virtualenvs.create false
+          make install-dependencies
+
+      - name: Lint and test code
+        run: |
+          make clean whitespace-format-check isort-check black-check pydocstyle flake8 pylint mypy test coverage
+
+      - run: echo "This job's status is ${{ job.status }}."

Makefile

@@ -1,7 +1,7 @@
 .PHONY: whitespace-format-check whitespace-format black-check pydocstyle black-format pylint flake8 isort-check isort-format mypy test coverage clean install-python create-environment delete-environment install-dependencies build-package
 
 PYTHON_ENVIRONMENT = "bibliography"
-PYTHON_VERSION = "3.10.7"
+PYTHON_VERSION = "3.8.5"
 SOURCE_FILES = *.py
 
 whitespace-format-check:

bibliography.py

@@ -20,7 +20,9 @@
 import dataclasses
 import re
 from typing import Dict
+from typing import List
 from typing import Optional
+from typing import Tuple
 
 # Dictionary mapping lower-case type of bibliographic entry to its proper spelling.
 ENTRY_TYPES = {
@@ -84,7 +86,7 @@ def capitalize(text):
     return output
 
 
-def find_matching_closing_brace(text: str) -> tuple[str, str]:
+def find_matching_closing_brace(text: str) -> Tuple[str, str]:
     """Finds closing brace in a string that matches '{' + string."""
     nesting = 1
     end = 0
@@ -257,7 +259,7 @@ def priority(self):
         return 0
 
 
-def parse_entries(text: str) -> list[Entry]:
+def parse_entries(text: str) -> List[Entry]:
     """Parses a list of bibliographic entries from a string."""
     entries = []
     while True:
@@ -269,7 +271,7 @@ def parse_entries(text: str) -> list[Entry]:
     return entries
 
 
-def read_file(file_name: str) -> tuple[list[str], str]:
+def read_file(file_name: str) -> Tuple[List[str], str]:
     """Reads content of a bibliography file."""
     comments = []
     lines = []
@@ -283,7 +285,7 @@ def read_file(file_name: str) -> tuple[list[str], str]:
     return comments, text
 
 
-def write_file(file_name: str, comments: list[str], entries: list[Entry]) -> None:
+def write_file(file_name: str, comments: List[str], entries: List[Entry]) -> None:
     """Writes text into a file."""
     with open(file_name, "w", encoding="utf-8") as file:
         if comments: