input: Write a python function to add, remove, and print words in a dictionary.
  assert d.add('apple', 'a fruit') == None
  assert d.data == {'apple': 'a fruit'}
  assert d.add('banana', 'another fruit') == None
  assert d.data == {'apple': 'a fruit', 'banana': 'another fruit'}
  assert d.remove('apple') == None
  assert d.data == {'banana': 'another fruit'}
  assert d.print_all() == None
output: class Dictionary:
      def __init__(self):
          self.data = {}
  
      def add(self, word, definition):
          self.data[word] = definition
  
      def remove(self, word):
          if word in self.data:
              del self.data[word]
  
      def print_all(self):
          for word, definition in self.data.items():
              print(f"{word}: {definition}")
  
  # Example usage
  d = Dictionary()
  assert d.add('apple', 'a fruit') == None
  assert d.data == {'apple': 'a fruit'}
  assert d.add('banana', 'another fruit') == None
  assert d.data == {'apple': 'a fruit', 'banana': 'another fruit'}
  assert d.remove('apple') == None
  assert d.data == {'banana': 'another fruit'}
  assert d.print_all() == None