title: subset h2o frame in python
body: <p>how can I subset a h2o frame in python.
  if x is a df &amp; Origin is a variable then in pandas we generally can do subsetting by</p>
  
  <pre><code>x[x.Origin == 'AAF']
  </code></pre>
  
  <p>but with h2o frame it gives the following error:
  "H2OResponseError: Server error java.lang.IllegalArgumentException:
    Error: Name lookup of 'x.hex' failed"</p>