title: Python - List of list from txt
body: <p>I'm new in programation and I am looking for a way to sort a list of list depending on the first digit of each line in a txt file. In the txt files the number are like this :</p>
  
  <p>0 1</p>
  
  <p>0 2</p>
  
  <p>1 2</p>
  
  <p>1 3</p>
  
  <p>1 0</p>
  
  <p>2 0</p>
  
  <p>2 3</p>
  
  <p>...</p>
  
  <p>And I want to create a list of lists like this : [[1,2], [2,3,0], [0,3,]...] I have try with append and sort but I can't get the answer I want. 
  Thanks for the help!</p>