title: python - calling a function from within itself
body: <p>The code I already have is for a bot that receives a mathematical expression and calculates it. Right now I have it doing multiply, divide, subtract and add. The problem though is I want to build support for parentheses and parentheses inside parentheses. For that to happen, I need to run the code I wrote for the expressions without parentheses for the expression inside the parentheses first. I was going to check for <code>"("</code> and append the expression inside it to a list until it reaches a <code>")"</code> unless it reaches another <code>"("</code> first in which case I would create a list inside a list. I would subtract, multiply and divide and then the numbers that are left I just add together.</p>
  
  <p>So is it possible to call a definition/function from within itself?</p>