title: select words excluding some specific ones - regular expression
body: <p>I am trying to match words from a sentence excluding the ones start with <code>@</code>.</p>
  
  <p>The original pattern which does not exclude the words starting with <code>@</code> is the following:</p>
  
  <pre><code>&gt;&gt;&gt; import re
  &gt;&gt;&gt; token_pattern_o='(?u)\\b\\w\\w+\\b'
  &gt;&gt;&gt; re.search(token_pattern_o, "@mutt")
  &lt;re.Match object; span=(1, 5), match='mutt'&gt;
  </code></pre>
  
  <p>Now I am just adding a negative lookahead for the exclusion:</p>
  
  <pre><code>&gt;&gt;&gt; token_pattern = '(?u)\\b^(?!@)\\w\\w+\\b'
  &gt;&gt;&gt; re.search(token_pattern, "#mutt")
  &gt;&gt;&gt; re.search(token_pattern, "@mutt")
  &gt;&gt;&gt; re.search(token_pattern, "mutt")
  &lt;re.Match object; span=(0, 4), match='mutt'&gt;
  &gt;&gt;&gt; re.search(token_pattern, "_mutt")
  &lt;re.Match object; span=(0, 5), match='_mutt'&gt;
  </code></pre>
  
  <p>The issue is, it is excluding every word starting with any special character.</p>
  
  <p>Is there a way to achieve what I am trying to achieve?</p>