curl --request GET \
  --url https://api.doppapp.com/v1/public/get_simplified_order_book

[
  {
    "order_books": [
      {
        "ask_iv": 123,
        "ask_price": 123,
        "base_currency": "<string>",
        "bid_iv": 123,
        "bid_price": 123,
        "delta": 123,
        "expiration_date": 123,
        "instrument_id": "<string>",
        "instrument_name": "<string>",
        "mark_price": 123,
        "side": "<string>",
        "strike_price": 123
      }
    ]
  }
]