Define a function lowest_score(tup) that takes a nested tuple like score_tuple, and returns a tuple with all the names of the students that have the lowest score in the tuple.

score_tup_1A = (('Peter', 10), ('Mary', 7), ('John', 8), ('Tim', 0), ('Jill', 8))

score_tup_1B = (('Jack', 7), ('Toby', 7), ('Amy', 4), ('Bobby', 4), ('Catherine', 8))

score_tup_1C = (('Sam', 8), ('Tom', 7), ('yvonne', 9))

def lowest_score(tup):
pass