title: Zipline-trader: Unknown syntax [{'sid': Equity(1576 [JPM])} -
body: <p>I am relatively new to Python and am working my way through the zipline-trader library. I came across a data structure that I am unfamiliar with and was wondering if you could help me access a certain element out of it.</p>
  <p>I ran a backtest on zipline-trader and have the results-DataFrame that has a column &quot;positions&quot; which includes the portfolio positions for a given day.</p>
  <p>Here is an example of the content of that column:</p>
  <pre><code>[{'sid': Equity(1576 [JPM]), 'amount': 39, 'cost_basis': 25.95397, 'last_sale_price': 25.94}, {'sid': Equity(2942 [UNH]), 'amount': 11, 'cost_basis': 86.62428999999999, 'last_sale_price': 86.58}]
  </code></pre>
  <p>The syntax I am unfamiliar with is the part &quot;Equity (1576 [JPM])&quot; - can anybody explain to me what this is? Also, can you please let me know how to access the &quot;[JPM]&quot;-part of it? Ultimately, what I am trying to do is access that cell of the DataFrame using a loc-function and producing the result &quot;{JPM: 1576, UNH: 2942}&quot;</p>
  <p>Thank you!</p>