title: How to add unicode character before a string? [Python]
body: <p>I want to be able to add a 'u' to a referenced string variable. I need to do this because when I am in a for loop, i can only access the string by a variable name.</p>
  
  <p>Is there a way to do this?</p>
  
  <pre><code>&gt;&gt;&gt; word = 'blahblah'
  &gt;&gt;&gt; list = ['blahblah', 'boy', 'cool']
  &gt;&gt;&gt; import marisa_trie
  &gt;&gt;&gt; trie = marisa_trie.Trie(list)
  &gt;&gt;&gt; word in trie
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
  TypeError: Argument 'key' has incorrect type (expected unicode, got str)
  &gt;&gt;&gt; 'blahblah' in trie
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
  TypeError: Argument 'key' has incorrect type (expected unicode, got str)
  &gt;&gt;&gt; u'blahblah' in trie
  True
  &gt;&gt;&gt; u"blahblah" in trie
  True
  &gt;&gt;&gt; u(word) in trie
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
  NameError: name 'u' is not defined
  &gt;&gt;&gt; uword in trie
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
  NameError: name 'uword' is not defined
  &gt;&gt;&gt; u+word in trie
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
  NameError: name 'u' is not defined
  &gt;&gt;&gt; word.u in trie
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
  AttributeError: 'str' object has no attribute 'u'
  </code></pre>