title: String eval() but ignore leading zeros (octal)
body: <p>I have a dynamically changing string which is evaluated using eval(). Now for numbers staring with '0' it is represented using octal system. 
  Eg. eval('030') = 24</p>
  
  <p>Now there's another thread with a similar issue (<a href="https://stackoverflow.com/questions/9843033/pythonic-way-to-eval-all-octal-values-in-a-string-as-integers">Pythonic way to eval all octal values in a string as integers</a>). The solution in the thread mentions a regular expression</p>
  
  <pre><code>re.sub(r'\b0+(?!\b)', '', some_string)
  </code></pre>
  
  <p>Now this works fine in most cases but when I have to evaluate for example '0.08', the aforementioned regex doesn't do the job well because it removes the zero after the decimal (it converst '0.08' tp 0.8' and sin(0.08) to sin(0.8) and so on...) . Given my limited knowledge in regex, I couldn't proceed with solving the issue. So basically, how do I modify the given regex so that it ignores zeroes immediately after decimal points? Thanks! </p>