title: Why isn't isnumeric working?
body: <p>I was going through a very simple python3 guide to using string operations and then I ran into this weird error:</p>
  
  <pre><code>In [4]: # create string
          string = 'Let\'s test this.'
  
          # test to see if it is numeric
          string_isnumeric = string.isnumeric()
  
  Out [4]: AttributeError                            Traceback (most recent call last)
           &lt;ipython-input-4-859c9cefa0f0&gt; in &lt;module&gt;()
                      3 
                      4 # test to see if it is numeric
                ----&gt; 5 string_isnumeric = string.isnumeric()
  
           AttributeError: 'str' object has no attribute 'isnumeric'
  </code></pre>
  
  <p>The problem is that, as far as I can tell, <code>str</code> <strong><a href="http://www.tutorialspoint.com/python/string_isnumeric.htm" rel="noreferrer">DOES</a></strong> have an attribute, <code>isnumeric</code>.</p>