input: 
  def pascal_triangle(n):
      """ Print out the Pascal's triangle for a given number of rows.
      >>> pascal_triangle(5)
      [1]
      [1, 1]
      [1, 2, 1]
      [1, 3, 3, 1]
      [1, 4, 6, 4, 1]
      True
      >>> pascal_triangle(0)
      False
      """
      trow = [1]
      y = [0]
      for x in range(max(n, 0)):
          print(trow)
          trow = [l + r for l, r in zip(trow + y, y + trow)]
      return n >= 1
  
  
output:     
      trow = [1]
      y = [0]
      for x in range(max(n, 0)):
          print(trow)
          trow = [l + r for l, r in zip(trow + y, y + trow)]
      return n >= 1
  