Solutions

leap_years = [year for year in range(1901, 2001) if year%4==0]

the_simpsons = [f"{character} Simpson" for character in characters if character in simpsons]

word_lengths = {word: len(word) for word in words if len(word)>=5}

ages_next_year = {person: age+1 if person!='Danny' else age for (person, age) in ages.items()}

vowels = {letter for letter in statement.lower() if letter in 'aeiou'}

overlap = {food for food in fruits if food in vegetables}

def format_name(honorific, candidate):
  return honorific + " " + candidate.get('name').split()[-1]

graduates = [format_name("Professor", candidate) if candidate.get('score')>=90 else format_name("Doctor", candidate) for candidate in phd_candidates if candidate.get('score') >=70]