title: Python reading only some lines of a text file
body: <p>I have text file like the following and what I would like to do it read three lines that start with 0 and three lines that start with 1 and so on until 30-40. And would like to print them on the same line. How could I accomplish this? Thank you very much!</p>
  
  <pre><code>0 something
  0 something2
  0 something3
  0 something4
  0 something5
  0 something6
  1 something
  1 something2
  1 something3
  1 something4
  1 something5
  1 something6
  </code></pre>
  
  <p>Desired output:</p>
  
  <pre><code>0 something something2 something3
  1 something something2 something3
  </code></pre>