fork download

copy

import asyncio
 
from collections import UserDict
from typing import Any
 
 
class AwaitDict(UserDict):
    def __init__(self, dict=None, /, **kwargs):
        self._await_task: dict[str, asyncio.Future] = {}
        super().__init__(dict=None, **kwargs)
 
    def __setitem__(self, key: str, item: Any):
        if future := self._await_task.get(key):
            if future.done():
                raise Exception('Expected value has not been received yet')
            future.set_result(item)
 
        super().__setitem__(key, item)
 
    def __getitem__(self, item: str) -> Any:
        if item in self._await_task:
            self._await_task.pop(item)
 
        return super().__getitem__(item)
 
    async def await_elem(self, key: str) -> Any:
        future = asyncio.Future()
        self._await_task[key] = future
        await future
        return future.result()
 
 
async def set_elem(aw: AwaitDict, key: str, value: Any):
    await asyncio.sleep(3)
    aw[key] = value
 
 
async def main():
    my_dict = AwaitDict()
    asyncio.create_task(
        set_elem(
            aw=my_dict,
            key='123',
            value=123
        )
    )
    data = await my_dict.await_elem('123')
    print(data)
    print(my_dict['123'])
 
asyncio.run(main())
 

Traceback (most recent call last):
  File "/usr/lib/python3.7/py_compile.py", line 143, in compile
    _optimize=optimize)
  File "<frozen importlib._bootstrap_external>", line 791, in source_to_code
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "./prog.py", line 8
    def __init__(self, dict=None, /, **kwargs):
                                  ^
SyntaxError: invalid syntax

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python3.7/py_compile.py", line 147, in compile
    raise py_exc
py_compile.PyCompileError:   File "./prog.py", line 8
    def __init__(self, dict=None, /, **kwargs):
                                  ^
SyntaxError: invalid syntax

Standard output is empty