using djanog model inheritance, given and id how to know which model does that id belong to? code example

Example 1: create models in django

from django.db import models
# Create your models here.

class Contact(models.Model):
    name = models.CharField(max_length=50)
    email = models.CharField(max_length=50)
    contact = models.CharField(max_length=50)
    content = models.TextField()
    def __str__(self):
        return self.name + ' ' + self.email

Example 2: how to connecct id's in the models of jdango

from django.db import models

class Musician(models.Model):
    first_name = models.CharField(max_length=50)
    last_name = models.CharField(max_length=50)
    instrument = models.CharField(max_length=100)

class Album(models.Model):
    artist = models.ForeignKey(Musician, on_delete=models.CASCADE)
    name = models.CharField(max_length=100)
    release_date = models.DateField()
    num_stars = models.IntegerField()