def get_by_diet(animal_d, diet): Consider a dictionary, animal_d, where the keys are names of animals, and the values are descriptions of their diets. The function should search in the dictionary for animals that are labeled as diet, put them into a list and return the sorted list.

o animal_d: a dictionary that maps animal names to their diet description.

o diet: the diet to search for.

o Return value: asciibetically sorted list of animals that are labeled as diet.

? Examples:

o get_by_diet({'deer':'herbivore', 'bear':'omnivore'}, 'herbivore') ? ['deer']

o get_by_diet({'lion':'carnivore', 'penguin':'piscivore'}, 'omnivore') ? [ ]