fetching data from multiple tables using related name in django

1from App.models import Student, Subject
2def myFunc():
3    students = Student.objects.all()
4    for student in students:
5        subj = student.subject.sub
6
7def myFunc2():
8    subjects = Subject.objects.all()
9    for subject in subjects:
10        student_name = subject.student.nm
11

1Order.objects.select_related('account_customer').all() \
2    .values('customer_id', 'other_field_1', ...) \
3    .annotate(total_sales=Sum('total_price')) \
4    .filter(created_at__year=today.year, created_at__month=today.month)

1class Student(models.Model):
2    sid = models.BigIntegerField(primary_key=True)
3    nm = models.CharField(max_length=20, blank=True, null=True)
4    subject = models.ForeignKey("Subject", related_name="student", blank=True, null=True)
5
6class Subject(models.Model):
7    sub = models.CharField(max_length=30, blank=True, null=True)
8