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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 discover_nupnp(websession):
 """Discover bridges via NUPNP."""

    async with websession.get(URL_NUPNP) as res:
        return [Bridge(item['internalipaddress'], websession=websession)
                for item in (await res.json())]