Introduced --retries flag, made thorough refactoring

- updated sites list
- test scripts linting

tests/test_executors.py

@@ -2,11 +2,16 @@
 import pytest
 import asyncio
 import logging
-from maigret.executors import AsyncioSimpleExecutor, AsyncioProgressbarExecutor, \
-                              AsyncioProgressbarSemaphoreExecutor, AsyncioProgressbarQueueExecutor
+from maigret.executors import (
+    AsyncioSimpleExecutor,
+    AsyncioProgressbarExecutor,
+    AsyncioProgressbarSemaphoreExecutor,
+    AsyncioProgressbarQueueExecutor,
+)
 
 logger = logging.getLogger(__name__)
 
+
 async def func(n):
     await asyncio.sleep(0.1 * (n % 3))
     return n
@@ -20,6 +25,7 @@ async def test_simple_asyncio_executor():
     assert executor.execution_time > 0.2
     assert executor.execution_time < 0.3
 
+
 @pytest.mark.asyncio
 async def test_asyncio_progressbar_executor():
     tasks = [(func, [n], {}) for n in range(10)]
@@ -64,4 +70,4 @@ async def test_asyncio_progressbar_queue_executor():
     executor = AsyncioProgressbarQueueExecutor(logger=logger, in_parallel=10)
     assert await executor.run(tasks) == [0, 3, 6, 9, 1, 4, 7, 2, 5, 8]
     assert executor.execution_time > 0.2
-    assert executor.execution_time < 0.3
+    assert executor.execution_time < 0.3