How to write test case for sending email

Here is the simple view for creating user and staff model.After creating user and staff, it sends the html email to the user's email to fill up the details and the view works fine. Now I want to write test case for this view and tried like this below but i got stuck on how can i write test to check whether the email will be sent or not after saving staff model, to the users. models.py

class Staff(models.Model):
    user = models.OneToOneField(get_user_model(), on_delete=models.CASCADE, related_name='staff')
    name = models.CharField(max_length=255, blank=True, null=True)
    organization = models.ForeignKey(Organization, on_delete=models.SET_NULL,related_name='staff')
    position = models.ForeignKey(Position, on_delete=models.SET_NULL,related_name='staff')
    .......

views.py

def register_staff(request):
    form = RegisterStaffForm()
    if request.method == 'POST':
        form = RegisterStaffForm(request.POST)
        if form.is_valid():
            name = form.cleaned_data['name']
            organization = form.cleaned_data['organization']
            position = form.cleaned_data['position']
            ......
            user = form.save(commit=False)
            user.is_staff = True
            user.is_active = True
            user.save()

            # creating staff model with user data

            Staff.objects.create(user=user, name=name, organization=organization, position=position,....)

            # sending html_email to the user
            config = EmailConfiguration.objects.order_by('-date').first()
            backend = EmailBackend(host=config.email_host, port=config.email_port, username=config.email_host_user,
                                   password=config.email_host_password, use_tls=config.email_use_tls)

            subject, from_email, to = "Staff Details", config.email_host_user, user.email
            text_content = "Staff Details "
            site = get_current_site(request)
            html_content = render_to_string('send_email.html',
                                            {'user': user, 'site_domain': site,})
            msg = EmailMultiAlternatives(subject, text_content, from_email, [to],connection=backend)
            msg.attach_alternative(html_content, "text/html")
            msg.send()

tests.py

class StaffTestCase(TestCase):

    def setUp(self):
        self.position = Position.objects.create(title='Developer')
        self.org = Organization.objects.create(name='name')
        self.user = get_user_model().objects.create_user(username='username01',password='Admin@321',email='abc@xyz.com',is_staff=True)
        self.staff = Staff.objects.create(user=self.user,position=self.position,organization=self.org,name='Julia')

        self.client = Client()

    def test_view_staffs(self):
        self.client.login(username='username01', password='Admin@321')
        response = self.client.get(reverse('app:view_staff_users'))
        self.assertEqual(response.status_code, 200)

    def add_staff(self):
        self.client.login(username='username01', password='Admin@321')
        url = reverse('app:register_staff')
        response = self.client.post(url, {'user': self.user,'organization':'name1','position':'Designer','name':'Mark'})
        self.assertEqual(response.status_code, 302)

    def check_email_will_sent_or_not(self):
     ??