403 Forbidden error when making an ajax Post request in Django framework

data: {"csrfmiddlewaretoken" : "{{csrf_token}}"}

You see "403 (FORBIDDEN)", because you don`t send "csrfmiddlewaretoken" parameter.
In template each form has this: {% csrf_token %}.
You should add "csrfmiddlewaretoken" to your ajax data dictionary. My example is sending "product_code" and "csrfmiddlewaretoken" to app "basket" view "remove":



$(function(){
$('.card-body').on('click',function(){
$.ajax({
type: "post",
url: "{% url 'basket:remove'%}",
data: {"product_code": "07316", "csrfmiddlewaretoken" : "{{csrf_token}}" }
});
})
});

Another approach is to add X-CSRFTOKEN header with the "{{ csrf_token }}" value like in the following example:

$.ajax({
url: "{% url 'register_lowresistancetyres' %}",
type: "POST",
headers: {//<==
"X-CSRFTOKEN": "{{ csrf_token }}"//<==
},
data: $(example_form).serialize(),
success: function(data) {
//Success code
},
error: function () {
//Error code
}
});

this works for me

template.html

$.ajax({
url: "{% url 'XXXXXX' %}",
type: 'POST',
data: {modifica: jsonText, "csrfmiddlewaretoken" : "{{csrf_token}}"},
traditional: true,
dataType: 'html',
success: function(result){
window.location.href = "{% url 'XXX' %}";
}
});

view.py

def aggiornaAttivitaAssegnate(request):
if request.is_ajax():
richiesta = json.loads(request.POST.get('modifica'))