title: Creating a 2 Dimensional array with a space separated user input
body: <p>I am a beginner level coder in Python language. So, I need to create a 2D array list using Python. Here, the input should be with a space separated one. I have tried many ways such as import sys method, raw_input method,etc. These are the errors;
  arr[i][j]=[int(x) for x in sys.argv[1:]]</p>
  <p><strong>IndexError: list index out of range</strong></p>
  <p>Here is my code:</p>
  <pre><code>    import sys 
      n = int(input()) 
      arr=[] 
      for i in range(n):
         for j in range(3):
            arr[i][j]=[int(x) for x in sys.argv[1:]]
         
      for i in range(n):
         for j in range(3):
            print(arr[i][j])
  </code></pre>