title: TypeError: not all arguments converted during string formatting in CQL
body: <p>I'm trying to insert a variable string into a Cassandra table using the following code:</p>
  
  <pre><code>b64_enc = "R21haWw="
  class SimpleClient:
      session = None
  
      def create_schema(self):
          self.session.execute("""CREATE KEYSPACE raas WITH replication = {'class':'SimpleStrategy', 'replication_factor':3};""")
          self.session.execute("""
              CREATE TABLE raas.result (
                  userb64enc text PRIMARY KEY,
                  statusflag int,
                  statusstr text
              );
          """)
          log.info('Simplex keyspace and schema created.')
  
      def load_data(self):
  
          self.session.execute("""INSERT INTO raas.result (userb64enc, statusflag, statusstr) VALUES(%s,0,'Success');""",  (b64_enc))
          log.info('Data loaded.')
  </code></pre>
  
  <p>But I get a </p>
  
  <pre><code>TypeError: not all arguments converted during string formatting
  </code></pre>
  
  <p>message. I've also tried using ? in place of the %s, but I get the same error. Any idea on what the cause of this error is?</p>