title: How can I check if character in a string is a letter? (Python)
body: <p>I know about <code>islower</code> and <code>isupper</code>, but can you check whether or not that character is a letter?
  For Example:</p>
  
  <pre class="lang-py prettyprint-override"><code>&gt;&gt;&gt; s = 'abcdefg'
  &gt;&gt;&gt; s2 = '123abcd'
  &gt;&gt;&gt; s3 = 'abcDEFG'
  &gt;&gt;&gt; s[0].islower()
  True
  
  &gt;&gt;&gt; s2[0].islower()
  False
  
  &gt;&gt;&gt; s3[0].islower()
  True
  </code></pre>
  
  <p>Is there any way to just ask if it is a character besides doing <code>.islower()</code> or <code>.isupper()</code>?</p>