title: datetime.datetime is not JSON serializable
body: <p>I have a class in Python for retrieving all the columns in a table and return a JSON with this data.</p>
  
  <p>The problem is at least one of those columns is a datetime and I can't seem to understand how to serialize the columns so I can generate a valid JSON.</p>
  
  <p>My class is as follows:</p>
  
  <pre><code>class GetTodos(Resource):
      def get(self):
          con = cx_Oracle.connect('brunojs/bdpf5@127.0.0.1/orcl')
          cur = con.cursor()
          cur.execute("select * from organite_repository")
          r = [dict((cur.description[i][0], value) \
                  for i, value in enumerate(row)) for row in cur.fetchall()]
          cur.connection.close()
          return (r[0] if r else None) if None else r 
  </code></pre>
  
  <p>Any hints on this?</p>