title: Check numeric values from a dictionary by unit test
body: <p>I have a function </p>
  
  <blockquote>
    <p>read_value_from_text()</p>
  </blockquote>
  
  <p>that reads parameters from a config file and returns a dictionary in this form</p>
  
  <pre><code>{ key1 : value1, key2 : value2, ... , keyn : valuen }
  </code></pre>
  
  <p>the values (value1 ... valuen) are all strings that represent numbers. 
  I want to write a unit test that checks if all values (value1,...,valuen) are "numeric" ( float or integer). Can someone suggest an efficient way to do this?</p>