diff --git a/none/__init__.py b/none/__init__.py
index d18c45c9..f3a1c128 100644
--- a/none/__init__.py
+++ b/none/__init__.py
@@ -67,17 +67,30 @@ class NoneBot(CQHttp):
 _bot = None
 
 
-def init(config_object: Any = None) -> NoneBot:
+def init(config_object: Any = None) -> None:
+    """
+    Initialize NoneBot instance.
+
+    This function must be called at the very beginning of code,
+    otherwise the get_bot() function will return None and nothing
+    is gonna work properly.
+
+    :param config_object: configuration object
+    """
     global _bot
     _bot = NoneBot(config_object)
     if _bot.config.DEBUG:
         logger.setLevel(logging.DEBUG)
     else:
         logger.setLevel(logging.INFO)
-    return _bot
 
 
 def get_bot() -> NoneBot:
+    """
+    Get the NoneBot instance.
+
+    :raise ValueError: instance not initialized
+    """
     if _bot is None:
         raise ValueError('NoneBot instance has not been initialized')
     # noinspection PyTypeChecker
@@ -85,6 +98,7 @@ def get_bot() -> NoneBot:
 
 
 def run(host: str = None, port: int = None, *args, **kwargs) -> None:
+    """Run the NoneBot instance."""
     get_bot().run(host=host, port=port, *args, **kwargs)
 
 
diff --git a/none/helpers.py b/none/helpers.py
index 38179a20..49c366a8 100644
--- a/none/helpers.py
+++ b/none/helpers.py
@@ -6,9 +6,7 @@ from . import NoneBot, expression
 
 
 def context_id(ctx: Dict[str, Any]) -> str:
-    """
-    Calculate a unique id representing the current user.
-    """
+    """Calculate a unique id representing the current user."""
     src = ''
     if ctx.get('group_id'):
         src += f'/group/{ctx["group_id"]}'
@@ -22,9 +20,7 @@ def context_id(ctx: Dict[str, Any]) -> str:
 async def send(bot: NoneBot, ctx: Dict[str, Any],
                message: Union[str, Dict[str, Any], List[Dict[str, Any]]],
                *, ignore_failure: bool = True) -> None:
-    """
-    Send a message ignoring failure by default.
-    """
+    """Send a message ignoring failure by default."""
     try:
         if ctx.get('post_type') == 'message':
             await bot.send(ctx, message)
@@ -46,7 +42,5 @@ async def send(bot: NoneBot, ctx: Dict[str, Any],
 async def send_expr(bot: NoneBot, ctx: Dict[str, Any],
                     expr: Union[str, Sequence[str], Callable],
                     **kwargs):
-    """
-    Sending a expression message ignoring failure by default.
-    """
+    """Sending a expression message ignoring failure by default."""
     return await send(bot, ctx, expression.render(expr, **kwargs))
diff --git a/none/session.py b/none/session.py
index 156cf963..7ee3606c 100644
--- a/none/session.py
+++ b/none/session.py
@@ -14,16 +14,12 @@ class BaseSession:
     async def send(self,
                    message: Union[str, Dict[str, Any], List[Dict[str, Any]]],
                    *, ignore_failure: bool = True) -> None:
-        """
-        Send a message ignoring failure by default.
-        """
+        """Send a message ignoring failure by default."""
         return await send(self.bot, self.ctx, message,
                           ignore_failure=ignore_failure)
 
     async def send_expr(self,
                         expr: Union[str, Sequence[str], Callable],
                         **kwargs):
-        """
-        Sending a expression message ignoring failure by default.
-        """
+        """Sending a expression message ignoring failure by default."""
         return await send_expr(self.bot, self.ctx, expr, **kwargs)
diff --git a/none_demo/__init__.py b/none_demo/__init__.py
index 5d5fbe2d..629f4a8a 100644
--- a/none_demo/__init__.py
+++ b/none_demo/__init__.py
@@ -3,8 +3,8 @@ from os import path
 import none
 from none_demo import config
 
-bot = none.init(config)
-app = bot.asgi
+none.init(config)
+app = none.get_bot().asgi
 
 if __name__ == '__main__':
     none.load_builtin_plugins()