在字典python中创建格式化的值

Question

Hi I recently started programming and ran into a little problem with one of the exercises on exercism. The exercise: ( https://github.com/exercism/xpython/tree/master/grade-school ?)

I cannot get it to pass the last test. It demands that the output is in the following way:

sorted_students = { 3: ("Kyle",), 4: ("Christopher", "Jennifer",), 6: ("Kareem",) }

I store the information in a dictionary with the grades being the keys and the students contained in a set as values. The last test however wants the values in the dictionary to be some sort of list and I do not know how to create this. My solution so far outputs the correct values with additional []brackets around the values. The error I get is as follows:

{3: ('Kyle',), 4: ('Christopher', 'Jennifer'), 6: ('Kareem',)} != {3: [('Kyle',)], 4: [('Christopher',), ('Jennifer',)], 6: [('Kareem',)]}

My code so:

class School:
def __init__(self,name):
    self.name = name
    self.db={}

def add(self,student, grad):
    if grad not in self.db:
        self.db[grad]={student}
    else:
        self.db[grad].add(student)

def grade(self,grad):
    if grad not in self.db:
        return set()
    else:
        return self.db[grad]

def sort(self): #where I fail
    newdict={} #new dictionary 
    for i in self.db: 
        newdict[i]=[(k,) for k in self.db[i]] #converst from set to list
    return newdict

Answer 1

The test demands a dictionary that maps integer to tuples. Note the round parenthesis (this denotes a tuple).

in your sort method you want:

return {g:tuple(s for s in self.db[g]) for g in self.db}