title: Python determinant calculation(without the use of external libraries)
body: <p>I'm making a small matrix operations library as a programming challenge to myself(and for the purpose of learning to code with Python), and I've come upon the task of calculating the determinant of 2x2, 3x3 and 4x4 matrices.</p>
  
  <p>As far as my understanding of linear algebra goes, I need to implement the Rule of Sarrus in order to do the first 2, but I don't know how to tackle this Pythonically or for matrices of  larger size. Any hints, tips or guides would be much appreciated.</p>