title: whitespace in regular expression
body: <p>I have a question, can I say <code>\t</code> is equivalent to <code>\s+</code> in regular expression.?
  I have some lines of code :</p>
  
  <pre><code>&gt;&gt;&gt; b = '\tNadya Carson'
  &gt;&gt;&gt; c = re.compile(r'\s\s*')
  &gt;&gt;&gt; c
  &lt;_sre.SRE_Pattern object at 0x02729800&gt;
  &gt;&gt;&gt; c.sub('',b)
  'NadyaCarson'
  &gt;&gt;&gt; c = re.compile(r'\s\s+')
  &gt;&gt;&gt; c
  &lt;_sre.SRE_Pattern object at 0x027292F0&gt;
  </code></pre>
  
  <p>There is pattern object till here but when I want to substitute with no space, it still shows \t instead of substituting it: </p>
  
  <pre><code>&gt;&gt;&gt; c.sub('',b)
  '\tNadya Carson'
  </code></pre>
  
  <p>Why is the attribute sub not working in this case.? Thank you.!</p>