title: Regex with "r" read from file doesn't work correctly
body: <p>I might have pretty basic question about regex. I have the following regex, which when hardcoded int the application work fine, but then I read it with ConfigParser doesn't seem to work:</p>
  
  <pre><code>r"\[[+-]?\d+(?:\.\d+)?\]"
  </code></pre>
  
  <p>The way how I read it is :</p>
  
  <pre><code>Config = ConfigParser.ConfigParser()
  Config.read("test.conf")
  test_regex = Config.get("test","test_regex")
  search_pattern = re.compile(test_regex)
  
  test_result = search_pattern.findall(text_to_parse)
  </code></pre>
  
  <p>The part of the test.conf</p>
  
  <pre><code>[test]
  test_regex=r"\[[+-]?\d+(?:\.\d+)?\]"
  </code></pre>
  
  <p>The input for testing might be something as follows:</p>
  
  <pre><code>text_to_parse = " Here is the [TEST-DONE]" // Success: my regex is extracting [TEST-DONE]
  text_to_parse = " Here is the some text" // Failure my regex returns empty list
  </code></pre>
  
  <p>Any solution for this issue?
  Thanks a lot,<br>
  Serhiy.</p>
  
  <p>EDIT: was my attention error, as I mention in the comment to answer, but the solution of remotion of the r from regex when it's in the file helped a lot.</p>