title: pandas - removing rows that contain certain values
body: <p>I have imported a csv file, each column relates to the response to a question asked in a survey. If the response was 'does not apply' there is a value of -8, and if there was no answer there is a value of -9. I would like to remove all rows that contain a value of -8 or -9 for any of the questions.</p>
  
  <p>How would I go about this using pandas?</p>
  
  <p>eg.</p>
  
  <pre><code>GRSSWK  HAPPY   HIQUL11D    MARDY6  MARSTA  PUBLICR QHEALTH1    RELIG11
  -9       9      -9          2       5       -9      -9          2
  -9       8      -9          2       5       -9      -9          2
  -9      -9      -9          2       4       -9       4          2
  481      8       1          1       2        2       3          2
  885     -9       1          1       2        2       1          2
  </code></pre>
  
  <p>only the fourth row would remain.</p>