async def METHOD_NAME(aconn):
    cur = aconn.cursor()
    await ensure_table(cur, "id serial primary key, data text")
    data = "".join(choice(string.ascii_letters) for i in range(10 * 1024 * 1024))
    copy_data = data + "\n"
    async with cur.copy("copy copy_in (data) from stdin") as copy:
        await copy.write(copy_data)
    await cur.execute("select data from copy_in limit 1")
    assert (await cur.fetchone())[0] == data