title: how to obtain a selected part of a dictionary of dictionaries from Alphavantage
body: <p>I got the next endpoint from Alphavantage, but i would like to use the RSI number, for a list of stocks. ¿How can i get just the RSI?
  I'll appreciate your answers</p>
  <pre><code>{
  
  'Meta Data': {'1: Symbol': 'ABMD',
    '2: Indicator': 'Relative Strength Index (RSI)',
    '3: Last Refreshed': '2021-10-13',
    '4: Interval': 'weekly',
    '5: Time Period': 10,
    '6: Series Type': 'open',
    '7: Time Zone': 'US/Eastern Time'},
   'Technical Analysis: RSI': {'2021-10-13': {'RSI': '50.5159'},
    '2021-10-08': {'RSI': '44.3446'},
    '2021-10-01': {'RSI': '55.6364'},
    '2021-09-24': {'RSI': '58.2600'},
    '2021-09-17': {'RSI': '63.0876'},
    '2021-09-10': {'RSI': '68.3045'},
    '2021-09-03': {'RSI': '65.3299'},
    '2021-08-27': {'RSI': '61.9752'},
    '2021-08-20': {'RSI': '52.7723'},
    '2021-08-13': {'RSI': '64.7634'},
  </code></pre>