title: Format a mathematical expression from user input to python
body: <p>I want to be able convert the input of a mathematical expression from a user to the python format for math expressions. For example if the user input is: </p>
  
  <blockquote>
    <p>3x^2+5</p>
  </blockquote>
  
  <p>I want to be able to convert that into </p>
  
  <blockquote>
    <p>3*x**2+5</p>
  </blockquote>
  
  <p>so that I can user this expression in other functions. Is there any existing library that can accomplish this in Python?</p>