title: Return JSON response from Flask view
body: <p>I have a function that analyzes a CSV file with Pandas and produces a dict with summary information. I want to return the results as a response from a Flask view. How do I return a JSON response?</p>
  
  <pre><code>@app.route("/summary")
  def summary():
      d = make_summary()
      # send it back as json
  </code></pre>