title: Convert a math equation in string format to something workable in Python3
body: <p>So I have a function that takes a math equation in string format, and a list of numbers.</p>
  
  <p>The purpose of the function is to apply that function to each number (an exponent function), and return the result.</p>
  
  <p>For example, I am trying to pass "x**4" to it, and the list [4,3,2]</p>
  
  <p>The end result, of course, would be [256, 81, 16]</p>
  
  <p>How do you convert the string to a math equation while also keeping in mind that the string could be anything from "x*<em>2" or "x</em>*3".</p>