python check set for key code example

Example 1: python check if value exists in any key

>>> d = {'1': 'one', '3': 'three', '2': 'two', '5': 'five', '4': 'four'}
>>> 'one' in d.values()
True

Example 2: python how to check if a dictionary key exists

if word in data:
  return data[word]
else:
  return "The word doesn't exist. Please double check it."