Binance.get_depth

You're seeing just the function get_depth, go back to Binance module for more information.
Link to this function

get_depth(symbol, limit)

Retrieves the bids & asks of the order book up to the depth for the given symbol

Returns {:ok, %{bids: [...], asks: [...], lastUpdateId: 12345}} or {:error, reason}

Example

{:ok,
  %Binance.OrderBook{
    asks: [
      ["8400.00000000", "2.04078100", []],
      ["8405.35000000", "0.50354700", []],
      ["8406.00000000", "0.32769800", []],
      ["8406.33000000", "0.00239000", []],
      ["8406.51000000", "0.03241000", []]
    ],
    bids: [
      ["8393.00000000", "0.20453200", []],
      ["8392.57000000", "0.02639000", []],
      ["8392.00000000", "1.40893300", []],
      ["8390.09000000", "0.07047100", []],
      ["8388.72000000", "0.04577400", []]
    ],
    last_update_id: 113634395
  }
}