input: Write a function to create a dictionary where the keys are numbers between 1 and 15 (both included) and the values are the squares of the keys. If the given range is empty then return an empty dictionary.
  assert create_square_dict(1, 15) == {1: 1, 2: 4, 3: 9, 4: 16, 5: 25, 6: 36, 7: 49, 8: 64, 9: 81, 10: 100, 11: 121, 12: 144, 13: 169, 14: 196, 15: 225}
  assert create_square_dict(0, 0) == {}
  assert create_square_dict(-1, 1) == {0: 0, 1: 1}
  assert create_square_dict(5, 10) == {5: 25, 6: 36, 7: 49, 8: 64, 9: 81, 10: 100}
  assert create_square_dict(10, 5) == {}
output: def create_square_dict(start, end):
      if start > end:
          return {}
      return {i: i**2 for i in range(start, end + 1)}