Add example for importing a client from one file everywhere

Author: doluk

examples/import_client.py

@@ -0,0 +1,66 @@
+"""
+A basic example for a dedicated file to import a signed in client everywhere else. For example in Cogs of discord bots.
+To use the client in any other file use the following code:
+```py
+from import_client import abstractClient
+coc_client = await abstractClient.get_client()
+```
+or
+```py
+from import_client import abstractClient
+coc_client = await abstractClient.client
+```
+
+"""
+import asyncio
+import logging
+from typing import AsyncGenerator
+
+import coc
+from coc import Client
+
+# logging
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger("coc.http")
+logger.setLevel(logging.DEBUG)
+
+
+class AbstractClient:
+	"""Class holding the async generator used to get the client and login on demand"""
+
+	def __init__(self):
+		# Pass credentials here or use a venv etc. to avoid hard coding them
+		self.__async_gen = self.__yield_client()  # create the async generator
+
+	async def __yield_client(self) -> AsyncGenerator[coc.Client, None]:
+		"""Get the async generator which always yields the client"""
+
+		async with coc.Client(loop=asyncio.get_event_loop_policy().get_event_loop()) as client:
+			await client.login("EMAIL", "PASSWORD")  # be aware that hard coding credentials is bad practice!
+			while True:
+				try:
+					yield client
+				except GeneratorExit:
+					break
+
+	async def get_client(self) -> Client:
+		"""Get the actual logged in client"""
+		if not hasattr(self, '__async_gen') and not hasattr(self, '_AbstractClient__async_gen'):
+			self.__async_gen = self.__yield_client()  # create async generator if needed
+		coc_client = await self.__async_gen.__anext__()
+		return coc_client
+
+	@property
+	async def client(self) -> Client:
+		"""Get the actual logged in client"""
+		if not hasattr(self, '__async_gen') and not hasattr(self, '_AbstractClient__async_gen'):
+			self.__async_gen = self.__yield_client()  # create async generator if needed
+		coc_client = await self.__async_gen.__anext__()
+		return coc_client
+
+	async def shutdown(self):
+		"""Log out and close the ClientSession"""
+		await self.__async_gen.aclose()
+
+
+abstractClient = AbstractClient()