title: Invalid symbol - Binance Api
body: <p>I'm trying to scrape the Open Interest of all tickers by binance api. However, the function <code>client.futures_open_interest(symbol=every_symbol)</code>reported an &quot;APIError(code=-1121): Invalid symbol&quot; error.</p>
  <pre><code>from binance import Client, ThreadedWebsocketManager, ThreadedDepthCacheManager
  
  client = Client(apikey, secret)
  
  exchange_info = client.get_exchange_info()
  
  
  for i in range(1985):#Total number of tickers
      every_symbol = exchange_info['symbols'][i][&quot;symbol&quot;]
      oi = client.futures_open_interest(symbol=every_symbol)
      print(oi)
  </code></pre>
  <p>As Far As I Can Tell <code>symbol</code> requires str, like<code>(symbol=&quot;BTCUSDT&quot;)</code>, so I use <code>str()</code> into <code>exchange_info['symbols'][i][&quot;symbol&quot;]</code>,like this</p>
  <pre><code>str(exchange_info['symbols'][i][&quot;symbol&quot;])
  </code></pre>
  <p>But it didn't work as well<br />
  how to solve this problem?<br />
  thanks</p>