title: .join() error; Not sure why
body: <p>Since I don't want an array's indices to be separated by a comma, I wrote this code:</p>
  
  <pre><code>landscape2 = ''.join(landscape)
  </code></pre>
  
  <p>However, I got an error message saying "landscape2 = ''.join(landscape)
  TypeError: sequence item 0: expected str instance, list found"
  I don't know what this means, and I wondered if you could help.</p>