def _normalize_headers(headers):
    return dict(
        [
            (
                _convert_byte_str(key).lower(),
                NORMALIZE_SPACE.sub(_convert_byte_str(value), " ").strip(),
            )
            for (key, value) in headers.items()
        ]
    )
The software does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources.