title: Python loop code won't print with solver code, possible other problem?
body: <p>I'm trying to create a simple solver that fills in the 0's of the 3x3 grid. The numbers are from 1-9. Based on the advice advise I got from one user I tried to make the loop work but it still does not work?</p>
  <pre><code>import numpy as np
  
  grid = [[0, 2, 3],
          [4, 0, 5],
          [6, 7, 0]]
  
  def possible(number, grid):
      for x in grid:
          if number in x:
              return False
          else:
              return True
  
  def solve():    
      global grid
      for number in grid:
          for m in number:            
              if m == 0:
                  for number in range(1,10):
                      if possible(number, grid):
                          grid = number                        
                          solve()
                  return
      print(np.matrix(grid))
  
  solve()
  </code></pre>