Python - Dictionary within list

Question

I have a dictionary inside the list:

A dictionary can be used to provide a "dependency table". For example, dependencies of disciplines in college.

To do Calculus 3, I first need to do Calculus 2 and Vectors.
To do Calculus 2, I first need to do Calculus 1.
For Calculation 1, there is no prerequisite.
To do Vectors, there is no prerequisite.

This can be represented by the following dictionary:

dependencies = { 'calculus 3' ['calculus 2', 'vectors'] 'calculus 2' ['calculus 1'] }

(Disciplines without dependency need not be cited.)

Note that, in total, calculation 3 ends up having THREE effective prerequisites: calculation 1, calculation 2 and vectors.

This is because calculation 1 is not cited directly but is indirect requirement.

I need to create a function that shows this DIRECT dependency: I thought of something like this:

def mostra_dependencias_diretas(dicionario, materia):
    for chave, valor in dicionario.items():
        if chave == materia:
        print(valor)

def test_06_dependencias_diretas(self):
        simples = {
            'calculo3' : ['calculo2', 'vetores'],
            'calculo2' : ['calculo1']
        }

s1 = pega_saida(mostra_dependencias_diretas, simples, 'calculo3')   
self.assertEqual(sorted(s1.split()), ['calculo2', 'vetores'])
mas o meu esta assim:
AssertionError: Lists differ: ["'vetores']", "['calculo2',"] != ['calculo2', 'vetores']