title: DNA to RNA using str.translate()
body: <p>I'm trying to convert the DNA code into RNA code using Python...</p>
  
  <p>I write this:</p>
  
  <pre><code>print('Digite a sequência DNA a ser transcrita para RNA:')
  
  my_str = raw_input()
  print(my_str.replace('T', 'U'))
  </code></pre>
  
  <p>And it works, but.. now I need to convert <strong>A to U</strong>, <strong>T to A</strong>, <strong>G to C</strong> and <strong>C to G</strong>... I looked how I could do it, and did this:</p>
  
  <pre><code>print('Digite a sequência DNA a ser transcrita para RNA:')
  
  my_str = raw_input()
  
  
  RNA_compliment = {
      ord('A'): 'U', ord('T'): 'A',
      ord('G'): 'C', ord('C'): 'G'}
  
  my_str.translate(RNA_compliment)
  </code></pre>
  
  <p>But I get this error:</p>
  
  <pre><code>Traceback (most recent call last):
    File "rna2.py", line 15, in &lt;module&gt;
      my_str.translate(RNA_compliment)
  TypeError: expected a character buffer object
  </code></pre>
  
  <p>What i did wrong? </p>