Python syntaxerror await outside async function

Easy Call async functions in sequential code [Call coroutines in django views]

If you ever tried to call coroutines in Django views, you probably know that it returns a coroutine object. It is related to the fact that Django views are sequential code. When you call async functions in sequential code, the return value is a coroutine object.

Unfortunately, you can not simply call the async function with the await construct. If you try this, you get a SyntaxError: ‘await’ outside async function. In this tutorial, we learn how to call async functions in sequential code and apply this technique to call coroutines in Django views.

Call coroutines in django views

Let see the errors you get when you call async functions in sequential code. The sequential code we demonstrate the problem is Django views. Suppose you have coroutines declared with async syntax, and you want to call coroutines in Django views; that is, you want to call coroutines in sequential code.

For the sake of simplicity, suppose the coroutine with async syntax return a string. In the Django view, you want to call this coroutine, find the generated string and respond with text file whose content is this value.

Call async functions in sequential code – Always return coroutine object

It seems straightforward task. You naively try to write the following code:

data.py – The module with coroutine declared with async syntax

import asyncio async def msg(): await asyncio.sleep(2) return 'hello' 

urls.py

from django.urls import path from . import views urlpatterns = [ path('hello', views.hello, name='hello') ] 

views.py

from . import data def hello(request): ss = data.hello() return HttpResponse(ss,content_type='text/plain') 

However when you test the URL you get the following text file:

Text File at /hello

This example shows that you will always get a coroutine object when you call async functions in sequential code. It is nice, but it not what you want to do. You want to return the value generated from the async function.

‘await’ outside async function

Fortunately, You remember that you can use the await statement to get the generated from the async function and decide to modify the code to use await construct.

views.py

from . import data def hello(request): ss = await data.hello() return HttpResponse(ss,content_type='text/plain')

When test the code by accessing the hello url, you get:

SyntaxError: ‘await’ outside async function

$ ./manage.py runserver 0:8000 Performing system checks. Unhandled exception in thread . ss = await data.msg() ^ SyntaxError: 'await' outside async function

It does not solve the problem. Now, the code raises an exception. You get SyntaxError exception with a clear message ‘await’ outside async function .

async functions always return coroutine object

Well, You may think it straightforward to fix this issue. You decide to modify the code and convert the view function to coroutine with the async construct.

views.py

from . import data async def hello(request): ss = await data.hello() return HttpResponse(ss,content_type='text/plain') 

When test the code by accessing the hello url, you get, An exception is raised when accessing the url:

exception at /hello : exception ‘coroutine’ object has no attribute ‘get’

 AttributeError at /hello 'coroutine' object has no attribute 'get' 

Oops! As we see earlier, a function with async syntax will always return coroutine object. However, sometimes your API require that you provide a regular function and not a coroutine.

In this example, Django (at least, Django 2.15) expect you return a HttpResponse object. However, when it try to call the method get method of the HttpResponse object, It can not find this methode and raises this exception.

How to Call async functions in sequential code?

Let’s see how to call async functions in sequential code. we will use the asyncio module

First, we create a new event loop with asyncio.new_event_loop

loop = asyncio.new_event_loop()

The loop will be responsible for executing coroutine or the async functions we provide it. We can tell the loop to wait until the coroutine is completed and return the generated value using run_until_complete method.

ss = loop.run_until_complete( data.msg() )

We need to close the loop when we do not need the loop anymore, so the loop releases the unused resources.

Putting it all together, we get the following code:

Call async functions in sequential code

 from . import data def hello(request): loop = asyncio.new_event_loop() ss = loop.run_until_complete( data.msg() ) loop.close() return HttpResponse(ss,content_type='text/plain') 

Now, When test the code by accessing the hello url, you get, An exception is raised when accessing the URL, we get the expected contents.

Text File at /hello

We see the problems you get when you call async functions in sequential code and how to overcome the issue. What do you think? Do you have a better solution?

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SyntaxError: ‘await’ outside function

Hello I am new to python and am trying to work with a Dark Sky python API made by Detrous. When I run the demo code I am presented with an error:

forecast = await darksky.get_forecast( ^ SyntaxError: 'await' outside function 

forecast = await darksky.get_forecast( latitude, longitude, extend=False, # default `False` lang=languages.ENGLISH, # default `ENGLISH` units=units.AUTO, # default `auto` exclude=[weather.MINUTELY, weather.ALERTS] # default `[]` ) 

3 Answers 3

I think this answer will be useful for people who search the same question as me. To use async functions in synchronous context you can use event loop. You can write it from scratch for education purposes. You can start from this answer https://stackoverflow.com/a/51116910/14154287 And continue education with David Beazley books.

But developers of asyncio already did this for you.

import asyncio loop = asyncio.get_event_loop() forecast = loop.run_until_complete(darksky.get_forecast(. . )) loop.close() 

The await keyword can be used only in asynchronous functions and methods. You can read more on asynchronous code to understand why.

The solution, without having any details about what you want to accomplish and how, is to use darksky = DarkSky(API_KEY) instead of darksky = DarkSkyAsync(API_KEY) .

In newer versions of python (v3.7+), you can call async functions in sync contexts by using asyncio.run :

import asyncio forecast = asyncio.run(darksky.get_forecast(. )) 

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Syntaxerror: await outside function

Encountering the syntaxerror: await outside function error messages are inevitable.

Sometimes, this error message it’s quite frustrating, especially, if you don’t know how to fix it.

Fortunately, in this article, we’ll explore how to fix this error, and you’ll know why await is only valid in async functions .

What is “await” keyword?

The “await” keyword is used in a type of programming called asynchronous programming. It’s used when we want different tasks to run at the same time, which helps the computer use its resources more efficiently.

But remember, you can only use the “await” keyword inside a special kind of function called an asynchronous function.

What is “syntaxerror: ‘await’ outside function” error message?

The error message syntaxerror: ‘await’ outside function occurs when we are trying to use an await keyword outside of an async function or method.

Await is used in an async function or method to wait on other asynchronous tasks.

For example:

import asyncio async def my_async_function(): await asyncio.sleep(1) return "Hello, Welcome to Itsourcecode!" result = await my_async_function() print(result)

 File "C:\Users\pies-pc2\PycharmProjects\pythonProject\main.py", line 7 result = await my_async_function() ^^^^^^^^^^^^^^^^^^^^^^^^^ SyntaxError: 'await' outside function 

Therefore, if you are calling the “await” keyword outside of an async function or method, SyntaxError will arise.

So, in simple words, this error typically occurs when the await keyword is used outside of an asynchronous function.

Why does the “syntaxerror: await outside function” occur?

This error message occurs due to several reasons, such as:

This error message occurs due to several reasons, such as:

❌Using await in a Synchronous Function

When using await, it is essential to remember that it can only be used within asynchronous functions. If you mistakenly use await in a synchronous function, the interpreter will raise SyntaxError.

❌ Misplaced await Statement

Placing the await keyword outside of any function. In Python, every awaits statement should be enclosed within an asynchronous function.

❌ Using await in a Regular Block

Await keyword cannot be used in regular blocks such as if statements or loops. The error will be raised if you try to use it in such contexts.

Why can I only use the await keyword inside of async function?

The reason you can only use the await keyword inside of an async function because it ensures proper flow control and synchronization between asynchronous tasks.

If you mark a function as async and use the await keyword within it, you indicate to the interpreter that the function contains asynchronous operations and should be treated accordingly.

How to fix the “syntaxerror: await outside function”?

To fix the syntaxerror ‘await’ outside function , ensure that the await keyword is used inside an async function or method.

If you are calling an async function or method outside of an async function or method, you need to use the asyncio.run() method to call the async function or method.

Use the asyncio.run() method to call the async function or method

Incorrect code:

❌ import asyncio async def my_async_function(): await asyncio.sleep(1) return "Hello, Welcome to Itsourcecode!" result = await my_async_function() print(result)

Corrected code:

✅ import asyncio async def my_async_function(): await asyncio.sleep(1) return "Hello, Welcome to Itsourcecode!" result = asyncio.run(my_async_function()) print(result)

Hello, Welcome to Itsourcecode!

Conclusion

In conclusion, the error message syntaxerror: ‘await’ outside function occurs when we are trying to use an await keyword outside of an async function or method.

Await is used in an async function or method to wait on other asynchronous tasks.

To fix this error, ensure that the await keyword is used inside an async function or method.

This article already discussed what this error is all about and multiple ways to resolve this error.

By executing the solutions above, you can master this SyntaxError with the help of this guide.

You could also check out other SyntaxError articles that may help you in the future if you encounter them.

We are hoping that this article helps you fix the error. Thank you for reading itsourcecoders 😊

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SyntaxError: ‘await’ outside async function

So i’m trying to add a queue to my bot. but it gives me the error in the title. This is the command to add something to the queue:

@commands.command() async def remove(self, ctx, number): global queue try: del (queue[int(number)]) await ctx.send(f'Your queue is now `!`') except: await ctx.send("Your queue is either **empty** or **out of range**") 

And this is my code to play the queue (I tried it a different way but idk how to play the next song if the current one stops if its not in a function, so yeah thats why its like in a def)

 def queuePlayer(): YDL_OPTIONS = vc = ctx.voice_client FFMPEG_OPTIONS = with youtube_dl.YoutubeDL(YDL_OPTIONS) as ydl: global queue info = ydl.extract_info(f"ytsearch:", download=False) if 'entries' in info: video = info['entries'][0] else: video = info url2 = video['formats'][0]['url'] def convert(seconds): seconds = seconds % (24 * 3600) hour = seconds // 3600 seconds %= 3600 minutes = seconds // 60 seconds %= 60 return "%d:%02d:%02d" % (hour, minutes, seconds) print(video) video_url = video['url'] print(video_url) source = await discord.FFmpegOpusAudio.from_probe(url2, **FFMPEG_OPTIONS) vc.play(source) del (queue[0]) print(video['title']) track = video['title'] artist = video['channel'] duration = video['duration'] durationConv = convert(duration) thumbnail = video['thumbnail'] embedVar = discord.Embed(title="Now playing", description=":notes: <>".format(track), color=0x00ff00) embedVar.add_field(name="Artist", value=":microphone: <>".format(artist), inline=False) embedVar.add_field(name="Duration", value=f":hourglass_flowing_sand: ``", inline=False) embedVar.set_thumbnail(url=thumbnail) await ctx.send(embed=embedVar) t = duration while t: time.sleep(1) t -= 1 print(t) print("TIMER REACHED 0") if t == 0: print("T IS 0") await ctx.send("Playing next!") queuePlayer() queuePlayer() 

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