input: def Pascal_Triangle(n: int):
      """Generate and print a Pascal triangle with the given number of rows.
      >>> Pascal_Triangle(5)
      1 
      1 1 
      1 2 1 
      1 3 3 1 
      1 4 6 4 1 
      """
output:     
      if n <= 0:
          return
      triangle = [[1]]
      for i in range(1, n):
          row = [1]
          for j in range(1, i):
              row.append(triangle[i-1][j-1] + triangle[i-1][j])
          row.append(1)
          triangle.append(row)
      for row in triangle:
          print(" ".join(map(str, row)))
  