I have defined a custom user model using AbstractBaseUser class. Below is the implementation for your reference.

class UserManager(BaseUserManager):
    def create_user(self, email, firstname, lastname, contact, password):
        if not email:
            raise ValueError('You must provide an email address')
        if not contact:
            raise ValueError('You must provide a contact number')
        
        email = self.normalize_email(email)
        user = self.model(email=email, firstname=firstname, lastname=lastname, contact=contact)
        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_superuser(self, email, firstname, lastname, contact, password):
        user = self.create_user(email, firstname, lastname, contact, password)
        user.is_admin = True
        user.save(using=self._db)
        return user

class Users(AbstractBaseUser):
    id = models.AutoField(primary_key=True)
    firstname = models.CharField(max_length=50)
    lastname = models.CharField(max_length=50)
    contact = models.CharField(max_length=10, unique=True)
    email = models.EmailField(unique=True)
    created_at = models.DateTimeField(auto_now_add=True)
    is_staff = models.BooleanField(default=True)
    is_admin = models.BooleanField(default=False)

    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = ['firstname', 'lastname', 'contact']

    objects = UserManager()

    def save(self, *args, **kwargs):
        if not self.firstname or not self.lastname or not self.contact or not self.email or not self.password:
            raise ValueError('All required fields must be provided')
        super().save(*args, **kwargs)

    def __str__(self):
        return str(self.id) + '. ' + self.firstname + ' ' + self.lastname

    def has_perm(self, perm, obj=None):
        return self.is_admin

    def has_module_perms(self, app_label):
        return True
    
    class Meta:
        db_table = 'users'
        verbose_name_plural = 'Users'

Everything works well apart from setting password for a new user or updating same for an existing user in Django’s native Admin page. While setting password, it sets passwords in a plain text rather than hashing it. Refer below the screenshot.

How do I resolve this?