Created Scheduling Functions (markdown)

Scheduling-Functions.md

@@ -0,0 +1,43 @@
+Telethon doesn't come with scheduling builtin because it would be unnecessary bloat. If you don't want more dependencies, you can just use `asyncio` to schedule functions to run later or at a given time.
+
+For example, if you want to run `foo` after 10 minutes:
+
+```python
+async def foo():
+  print('hi')
+
+def foo_cb():
+  client.loop.create_task(foo())
+
+client.loop.call_later(10 * 60, foo_cb)
+```
+
+[`loop.call_later()`](https://docs.python.org/3/library/asyncio-eventloop.html#asyncio.loop.call_later) can only schedule synchronous functions (`call_cb`), but you can use `create_task` to spawn a background, asynchronous task.
+
+You can also run something "every N seconds". For example, to repeat `foo` every 10 minutes:
+
+```python
+async def foo():
+  print('hi')
+
+def foo_cb():
+  client.loop.create_task(foo())
+  client.loop.call_later(10 * 60, foo_cb)
+
+foo_cb()
+```
+
+This schedules itself again when it runs, so it is always running. It runs, 10 minutes pass, it schedules itself again, and repeat. This is similar to JavaScript's `setTimeout`.
+
+You can also use `while` loops:
+
+```python
+async def foo():
+  while True:
+    print('hi')
+    await sleep(10 * 60)
+
+client.loop.create_task(foo())
+```
+
+If you don't mind using other libraries, [`aiocron`](https://github.com/gawel/aiocron) is a good option. See https://crontab.guru/ to learn its time syntax.