input: Write a function to print a staircase of height 'n', where n is an integer. The staircase should be right-aligned and composed of '#' characters.
  def staircase(n): 
      for i in range(0, n): 
          for j in range(0, n - i - 1): 
              print(end=" ") 
          for j in range(0, i + 1): 
              print("#", end="") 
          print("\r") 
    
  assert staircase(5)==None
  assert staircase(3)==None
  assert staircase(0)==None
output: def staircase(n): 
      for i in range(0, n): 
          for j in range(0, n - i - 1): 
              print(end=" ") 
          for j in range(0, i + 1): 
              print("#", end="") 
          print()