title: Getting COUNT from sqlalchemy
body: <p>I have:</p>
  
  <pre><code>res = db.engine.execute('select count(id) from sometable')
  </code></pre>
  
  <p>The returned object is <code>sqlalchemy.engine.result.ResultProxy</code>.</p>
  
  <p>How do I get count value from <code>res</code>? </p>
  
  <p>Res is not accessed by index but I have figured this out as:</p>
  
  <pre><code>count=None
  for i in res:
      count = res[0]
      break
  </code></pre>
  
  <p>There must be an easier way right? What is it? I didn't discover it yet.
  Note: The db is a <code>postgres</code> db.</p>