input: Write a python function to remove entries where the value contains the word 'not' or 'bad'.
  assert clean_dict({'apple': 'This apple is not fresh.', 'orange': 'This orange has gone bad.', 'banana': 'This banana is too ripe.'}) == {'banana': 'This banana is too ripe.'}
  assert clean_dict({'pear': 'This pear is delicious.', 'grape': 'These grapes are fresh.', 'apple': 'This apple is not good.'}) == {'pear': 'This pear is delicious.', 'grape': 'These grapes are fresh.'}
  assert clean_dict({'kiwi': 'This kiwi is not ripe.', 'mango': 'This mango is perfectly ripe.', 'peach': 'This peach has gone bad.'}) == {'mango': 'This mango is perfectly ripe.'}
output: def clean_dict(d):
      return {k: v for k, v in d.items() if 'not' not in v.lower() and 'bad' not in v.lower()}