title: How do you define a function to return the sum of two functions?
body: <p>I am working on a Python lesson about functions.
  I created a simple square root function:</p>
  
  <pre><code>def sqrt(x):
       return x ** 0.5
  
  print(sqrt(9))
  </code></pre>
  
  <p>Now, I wanted to create a function which can call <strong>sqrt</strong> (as a parameter) twice:</p>
  
  <pre><code>def add_function(func, x):
      return((func, x) + (func, x))
  
      print(add_function(sqrt, 9))
  </code></pre>
  
  <p>However, this gets a syntax error.  In my mind, the <code>add_function</code> should return the <code>sqrt</code> function with the argument 9 added to the same. </p>
  
  <p>I am looking for a some enlightenment. </p>