input: Write a function to print a staircase of height 'n', where n is an integer. Each level of the staircase should be composed of '#' characters, with spaces on the left side to align the staircase to the right.
  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()
  
  assert staircase(5)
  assert staircase(3)
  assert staircase(0)
  assert staircase(7)
  assert staircase(1)
output: def staircase(n):
      for i in range(n):
          print(' ' * (n - i - 1) + '#' * (i + 1))