title: Python Regex to capture single character alphabeticals
body: <p>Why doesn't the below regex print True? </p>
  
  <pre><code>print re.compile(r'^\b[a-z]\b$').search('(s)')
  </code></pre>
  
  <p>I want to match single char alphabeticals that may have non alphanumeric characters before and after, but do not have any more alphanumeric characters anywhere in the string. So the following should be matches:</p>
  
  <pre><code>'b'
  'b)'
  '(b)'
  'b,
  </code></pre>
  
  <p>and the following should be misses:</p>
  
  <pre><code>'b(s)'
  'blah(b)'
  'bb)'
  'b-b'
  'bb'
  </code></pre>
  
  <p>The solutions <a href="https://stackoverflow.com/questions/16169815/python-regex-find-all-single-alphabetical-characters">here</a> don't work.</p>