commit 8bf0712fcbdedd95fa9e760a29e656b40ca98231
Author: Bùi Thành Nhân <hi@imnhan.com>
Date:   Thu Aug 20 22:21:05 2020 +0700

    enforce black/isort conf, use abc for workers

diff --git a/.isort.cfg b/.isort.cfg
new file mode 100644
index 0000000..ba2778d
--- /dev/null
+++ b/.isort.cfg
@@ -0,0 +1,6 @@
+[settings]
+multi_line_output=3
+include_trailing_comma=True
+force_grid_wrap=0
+use_parentheses=True
+line_length=88
diff --git a/pyproject.toml b/pyproject.toml
index ca51916..da61574 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -31,3 +31,7 @@ ipdb = "^0.13.3"
 [build-system]
 requires = ["poetry>=0.12"]
 build-backend = "poetry.masonry.api"
+
+[tool.black]
+line-length = 88
+target-version = ['py37']
diff --git a/src/pytaku/__init__.py b/src/pytaku/__init__.py
index 39751a3..f320f42 100644
--- a/src/pytaku/__init__.py
+++ b/src/pytaku/__init__.py
@@ -35,6 +35,7 @@ def dev():
 
 def migrate():
     import argparse
+
     from .database.migrator import migrate
 
     argparser = argparse.ArgumentParser()
diff --git a/src/pytaku/database/migrator.py b/src/pytaku/database/migrator.py
index 58603a9..f9a1909 100644
--- a/src/pytaku/database/migrator.py
+++ b/src/pytaku/database/migrator.py
@@ -6,7 +6,6 @@
 from . import migrations
 from .common import DBNAME, get_conn, run_sql
 
-
 """
 Forward-only DB migration scheme held together by duct tape.
 
diff --git a/src/pytaku/scheduler.py b/src/pytaku/scheduler.py
index d65fa33..d6183d2 100644
--- a/src/pytaku/scheduler.py
+++ b/src/pytaku/scheduler.py
@@ -1,11 +1,8 @@
 import time
+from abc import ABC, abstractmethod
 from datetime import datetime, timedelta
 
-from .persistence import (
-    delete_expired_tokens,
-    find_outdated_titles,
-    save_title,
-)
+from .persistence import delete_expired_tokens, find_outdated_titles, save_title
 from .source_sites import get_title
 
 now = datetime.now
@@ -23,7 +20,7 @@ def main_loop():
         time.sleep(5)
 
 
-class Worker:
+class Worker(ABC):
     interval = timedelta(days=1)
 
     def __init__(self):
@@ -32,8 +29,9 @@ def __init__(self):
     def should_run(self):
         return now() - self.last_run >= self.interval
 
+    @abstractmethod
     def run(self):
-        raise NotImplementedError()
+        pass
 
     def after_run(self):
         self.last_run = now()