Ajuda no model do Django

from django.db import models
from django.urls import reverse

from apps.diario.models import CadastroTurma
from apps.empresa.models import Empresa



class Alunos(models.Model):
    matricula = models.PositiveIntegerField(null=False,blank=False,unique=True,default=0,verbose_name=''''Matricula'''')
    senha = models.IntegerField(null=False, blank=False,verbose_name=''''Senha'''')
    nome=models.CharField(max_length=100, null=False, blank=False,verbose_name=''''NOME'''')
    cpf = models.IntegerField(null=False, blank=False,verbose_name=''''CPF'''',unique=True)
    rg = models.IntegerField(null=False, blank=False,verbose_name=''''RG'''')
    turma=models.ForeignKey(CadastroTurma,null=False, blank=False, on_delete=models.PROTECT,verbose_name=''''TURMA'''')
    data_nascimento=models.DateField(blank=True, null=True, verbose_name=''''DATA DE NASCIMENTO'''')
    cel=models.IntegerField(null=False, blank=False,verbose_name=''''CELULAR'''')
    tel=models.IntegerField(null=False, blank=False,verbose_name=''''TELEFONE'''')
    mae = models.CharField(max_length=100, null=False, blank=False,verbose_name=''''NOME DA MÃE'''')
    cpf_responsavel=models.IntegerField(null=False, blank=False,verbose_name=''''CPF DO RESPONSÁVEL'''',unique=True)
    pai =models.CharField(max_length=100, null=True, blank=True,verbose_name=''''NOME DO PAI'''')
    endereco =models.CharField(max_length=100, null=False, blank=False,verbose_name=''''ENDEREÇO'''')
    cidade =models.CharField(max_length=100, null=False, blank=False,verbose_name=''''CIDADE'''')
    bairro =models.CharField(max_length=100, null=False, blank=False,verbose_name=''''BAIRRO'''')
    empresa = models.ForeignKey(Empresa, on_delete=models.PROTECT, null=True, blank=True)


    def get_absolute_url(self):
        return reverse(''''financ_alunos'''')


    def __str__(self):
        return self.nome

class Bimestre(models.Model):
    bimestre = models.IntegerField()



class ControleFaltas(models.Model):
    data = models.DateField(''''Data'''')
    bimestre = models.ForeignKey(Bimestre,on_delete=models.PROTECT,null=False, blank=False)
    alunos=models.ForeignKey(Alunos,null=False, blank=False, on_delete=models.PROTECT)
    faltas = models.BooleanField(''''Faltas'''')

    def __str__(self):
        return ''''{}''''.format(self.alunos)

class ControleNotas(models.Model):
    alunos=models.ForeignKey(Alunos,null=False, blank=False, on_delete=models.PROTECT)
    bimestre = models.ForeignKey(Bimestre, on_delete=models.PROTECT, null=False, blank=False)
    p1 = models.FloatField(''''p1'''',null=True, blank=True, default=0)
    p2 = models.FloatField(''''p2'''',null=True, blank=True,default=0)
    recuperacao =models.FloatField(''''Recuperacao'''', null=True, blank=True,default=0)
    media = models.FloatField(''''Média'''',null=True, blank=True,default=0)

    def __str__(self):
        return ''''{}''''.format(self.alunos)