title: Error: Cursor' object has no attribute '_last_executed
body: <p>I have this cursor</p>
  
  <pre><code>cursor.execute("SELECT price FROM Items WHERE itemID = ( 
                    SELECT item_id FROM Purchases 
                    WHERE purchaseID = %d AND customer_id = %d)", 
                    [self.purchaseID, self.customer])
  </code></pre>
  
  <p>I get this error</p>
  
  <pre><code>'Cursor' object has no attribute '_last_executed'
  </code></pre>
  
  <p>But when I try this: </p>
  
  <pre><code>cursor.execute("SELECT price FROM Items WHERE itemID = ( 
                    SELECT item_id FROM Purchases 
                    WHERE purchaseID = 1 AND customer_id = 1)", 
                    )
  </code></pre>
  
  <p>there is no error. How do I fix this?</p>