title: Aggregation into mean, min and max of a List of Dictionaries using Python 3.7 and not using pandas
body: <p>I have the following data</p>
  <pre><code>data = [{'item': 'A', 'price': '$52'},
  {'item': 'B', 'price': '$21'},
  {'item': 'C', 'price': '$35'},
  {'item': 'A', 'price': '$52'},
  {'item': 'A', 'price': '$52'},
  {'item': 'B', 'price': '$21'}]
  </code></pre>
  <p>How do I aggregate item A, B and C this without using pandas and only python 3+
  Appreciate any links to help me out here.</p>
  <p>Expected output is</p>
  <pre><code>A $156
  B $42
  C $35
  </code></pre>
  <p>I have tried the following code:</p>
  <pre><code>for key, group in itertools.groupby(sorted_data, lambda item: item['item']):
      print(key, sum([item[&quot;item&quot;] for item in group]))
  </code></pre>
  <p>I get the following error:</p>
  <pre><code>TypeError: unsupported operand type(s) for +: 'int' and 'str'
  </code></pre>
  <p>Are there any simpler solutions to this:</p>