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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:
 def stream( streaming_fn, status=200, headers=None, content_type="text/plain; charset=utf-8", ):
 """Accepts an coroutine `streaming_fn` which can be used to write chunks to a streaming response. Returns a `StreamingHTTPResponse`. Example usage:: @app.route("/") async def index(request):
 async def streaming_fn(response):
 await response.write('foo') await response.write('bar') return stream(streaming_fn, content_type='text/plain') :param streaming_fn: A coroutine accepts a response and writes content to that response. :param mime_type: Specific mime_type. :param headers: Custom Headers. """

    return StreamingHTTPResponse(
        streaming_fn, headers=headers, content_type=content_type, status=status
    )