new_contents: z = len
  u = x = y = r = 0
  def v():
      global u
      if z(r) < 3:
          if y < 1:
              c, n = r
          else:
              n, c = r
          s = 0
      else:
          l, c, n = r
          s = l[x - 1] + l[x] + (l[x+1] if x == z(l) else 0)
  
      u = s + {x : sum(c[x - 1:x+2] + n[x - 1:x + 2]) - c[x],
          0 : n[0] + n[1] + c[1],
          z(c) - 1 : n[x - 1] + n[x] + c[x - 1]
          }[x]
  
  
  def d(w):
      global r, x, y
      a = list.append
      m = [[int(i) for i in l.strip()] for l in open(w)]
  
      n = range(1, z(m))
      
      r = m[0:2]
      v() 
      e = [{u:0,2: r[0][0], 3: 1}[u]]
  
      for x in n:
          v()
          a(e, {u:0,2: r[1][x], 3: 1}[u])
      o = [e]
  
      for y in n:
          r = m[y - 1:y + 2]
          x = 0
          v()  
          e = [{u:0,2: r[1][1], 3: 1}[u]]
  
          for x in n:
              v()
              a(e, {u:0,2: r[1][x], 3: 1}[u])
          a(o, e)
  
      f = open(w, 'w')
      f.write('\n'.join(''.join(map(str, q)) for q in o))
  
subject: Create game_of_life.py