title: Python list append
body: <p>I want to store the intermediate values of a variable in Python. This variable is updated in a loop. When I try to do this with a <code>list.append</code> command, it updates every value in the list with the new value of the variable. How should I do it ?</p>
  
  <pre><code>while (step &lt; maxstep):
      for i in range(100):    
          x = a*b*c
          f1 += x
      f2.append(f1)
      print f2
      raw_input('&lt;&lt;')
      step += 1
  </code></pre>
  
  <p>Expected output</p>
  
  <pre><code>[array([-2.03,-4.13])]
  &lt;&lt;
  [array([-2.03,-4.13]),array([-3.14,-5.34])]
  </code></pre>
  
  <p>Printed output</p>
  
  <pre><code>[array([-2.03,-4.13])]
  &lt;&lt;
  [array([-3.14,-5.34]),array([-3.14,-5.34])]
  </code></pre>
  
  <p>Is there a different way of getting what I want in python?</p>