diff --git a/aio_pika/__init__.py b/aio_pika/__init__.py
index 516eb51e..e18002a4 100644
--- a/aio_pika/__init__.py
+++ b/aio_pika/__init__.py
@@ -13,12 +13,8 @@
 from .robust_queue import RobustQueue
 
 
-try:
-    from importlib.metadata import Distribution
-    __version__ = Distribution.from_name("aio-pika").version
-except ImportError:
-    import pkg_resources
-    __version__ = pkg_resources.get_distribution("aio-pika").version
+from importlib.metadata import Distribution
+__version__ = Distribution.from_name("aio-pika").version
 
 
 __all__ = (
diff --git a/aio_pika/abc.py b/aio_pika/abc.py
index 1f27022b..95873337 100644
--- a/aio_pika/abc.py
+++ b/aio_pika/abc.py
@@ -1,6 +1,5 @@
 import asyncio
 import dataclasses
-import sys
 from abc import ABC, abstractmethod
 from dataclasses import dataclass
 from datetime import datetime, timedelta
@@ -9,16 +8,10 @@
 from types import TracebackType
 from typing import (
     Any, AsyncContextManager, AsyncIterable, Awaitable, Callable, Dict,
-    Generator, Iterator, Mapping, Optional, Tuple, Type, TypeVar, Union,
-    overload,
+    Generator, Iterator, Literal, Mapping, Optional, Tuple, Type, TypedDict,
+    TypeVar, Union, overload,
 )
 
-
-if sys.version_info >= (3, 8):
-    from typing import Literal, TypedDict
-else:
-    from typing_extensions import Literal, TypedDict
-
 import aiormq.abc
 from aiormq.abc import ExceptionType
 from pamqp.common import Arguments, FieldValue
diff --git a/aio_pika/queue.py b/aio_pika/queue.py
index 88ad4b20..fca449c9 100644
--- a/aio_pika/queue.py
+++ b/aio_pika/queue.py
@@ -1,10 +1,9 @@
 import asyncio
-import sys
 from asyncio import Future
 from functools import partial
 from types import TracebackType
 from typing import (
-    Any, Awaitable, Callable, Optional, Type, cast, overload,
+    Any, Awaitable, Callable, Literal, Optional, Type, cast, overload,
 )
 
 import aiormq
@@ -23,12 +22,6 @@
 from .tools import CallbackCollection, create_task, ensure_awaitable
 
 
-if sys.version_info >= (3, 8):
-    from typing import Literal
-else:
-    from typing_extensions import Literal
-
-
 log = get_logger(__name__)
 
 
@@ -546,7 +539,6 @@ def __aiter__(self) -> "AbstractQueueIterator":
     async def __aenter__(self) -> "AbstractQueueIterator":
         if not hasattr(self, "_consumer_tag"):
             await self.consume()
-
         return self
 
     async def __aexit__(
diff --git a/aio_pika/robust_connection.py b/aio_pika/robust_connection.py
index c1a28368..091f7bc4 100644
--- a/aio_pika/robust_connection.py
+++ b/aio_pika/robust_connection.py
@@ -103,10 +103,6 @@ async def _on_connected(self) -> None:
                 except Exception:
                     log.exception("Failed to reopen channel")
                     raise
-        except asyncio.CancelledError:
-            # In python 3.7 asyncio.CancelledError inherited
-            # from Exception and this needed for catch it first
-            raise
         except Exception as e:
             closing = self.loop.create_future()
             closing.set_exception(e)
diff --git a/aio_pika/tools.py b/aio_pika/tools.py
index daec83ea..890a794b 100644
--- a/aio_pika/tools.py
+++ b/aio_pika/tools.py
@@ -19,25 +19,12 @@
 
 def iscoroutinepartial(fn: Callable[..., Any]) -> bool:
     """
-    Function returns True if function is a partial instance of coroutine.
-    See additional information here_.
-
-    :param fn: Function
-    :return: bool
-
-    .. _here: https://goo.gl/C0S4sQ
-
+    Use Python 3.8's inspect.iscoroutinefunction() instead
     """
-
-    while True:
-        parent = fn
-
-        fn = getattr(parent, "func", None)  # type: ignore
-
-        if fn is None:
-            break
-
-    return asyncio.iscoroutinefunction(parent)
+    warnings.warn(
+        "Use inspect.iscoroutinefunction() instead.", DeprecationWarning
+    )
+    return asyncio.iscoroutinefunction(fn)
 
 
 def _task_done(future: asyncio.Future) -> None:
@@ -57,8 +44,8 @@ def create_task(
 ) -> Awaitable[T]:
     loop = loop or asyncio.get_event_loop()
 
-    if iscoroutinepartial(func):
-        task = loop.create_task(func(*args, **kwargs))      # type: ignore
+    if inspect.iscoroutinefunction(func):
+        task = loop.create_task(func(*args, **kwargs))
         task.add_done_callback(_task_done)
         return task
 
@@ -260,7 +247,7 @@ def ensure_awaitable(
     if inspect.iscoroutinefunction(func):
         return func
 
-    if inspect.isfunction(func) and not iscoroutinepartial(func):
+    if inspect.isfunction(func):
         warnings.warn(
             f"You probably registering the non-coroutine function {func!r}. "
             "This is deprecated and will be removed in future releases. "
diff --git a/docs/source/conf.py b/docs/source/conf.py
index 3417ebf4..92a0e9d5 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -23,12 +23,8 @@
 
 
 # noinspection PyUnresolvedReferences
-try:
-    from importlib.metadata import Distribution
-    __version__ = Distribution.from_name("aio-pika").version
-except ImportError:
-    import pkg_resources
-    __version__ = pkg_resources.get_distribution("aio-pika").version
+from importlib.metadata import Distribution
+__version__ = Distribution.from_name("aio-pika").version
 
 sys.path.insert(0, os.path.abspath(os.path.dirname("__file__")))