title: 'Decimal' object is not iterable when trying to extend list
body: <p>I have the following -</p>
  
  <pre><code>db = mariadb.connect(host=host,
                       user=someuser,
                       passwd=somepass)
  
  cursor = db.cursor(mariadb.cursors.DictCursor)
  
  #Get the top 5 largest tables inside of the database
  cursor.execute('SELECT table_schema as `Database`, table_name AS `Table`, round(((data_length + index_length) / 1024 / 1024), 2) `Size in MB`  FROM information_schema.TABLES  ORDER BY (data_length + index_length) DESC LIMIT 5;')
  data = cursor.fetchall()
  
  for item in data:
     dbsize.extend(float(item['Size in MB']))
  </code></pre>
  
  <p>This is giving me the following error - </p>
  
  <p><code>'Decimal' object is not iterable</code></p>
  
  <p>If I just print them (instead of adding them to a list) it prints out the correct values.  How can I get this code to add each item to this list successfully?  I tried changing them to floats, but got the same error.</p>
  
  <p>Thanks.</p>