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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def iter( self, url: Union[str, methods], data: Optional[MutableMapping] = None, headers: Optional[MutableMapping] = None, *, limit: int = 200, iterkey: Optional[str] = None, itermode: Optional[str] = None, minimum_time: Optional[int] = None, as_json: Optional[bool] = None ) -> AsyncIterator[dict]: """ Iterate over a slack API method supporting pagination When using :class:`slack.methods` the request is made `as_json` if available Args: url: :class:`slack.methods` or url string data: JSON encodable MutableMapping headers: limit: Maximum number of results to return per call. iterkey: Key in response data to iterate over (required for url string). itermode: Iteration mode (required for url string) (one of `cursor`, `page` or `timeline`) minimum_time: Minimum elapsed time (in seconds) between two calls to the Slack API (default to 0). If not reached the client will sleep for the remaining time. as_json: Post JSON to the slack API Returns: Async iterator over `response_data[key]` """

        itervalue = None

        if not data:
            data = {}

        last_request_time = None
        while True:
            current_time = time.time()
            if (
                minimum_time
                and last_request_time
                and last_request_time + minimum_time > current_time
            ):
                await self.sleep(last_request_time + minimum_time - current_time)

            data, iterkey, itermode = sansio.prepare_iter_request(
                url,
                data,
                iterkey=iterkey,
                itermode=itermode,
                limit=limit,
                itervalue=itervalue,
            )
            last_request_time = time.time()
            response_data = await self.query(url, data, headers, as_json)
            itervalue = sansio.decode_iter_request(response_data)
            for item in response_data[iterkey]:
                yield item

            if not itervalue:
                break