[Answer]-Django display ManyToManyField as a form field

You are skipping a step. You first need to create a form.

In forms.py you can create a ModelForm. A ModelForm is a form based on your model:

from django.forms import ModelForm
from myapp.models import Act

class ActForm(ModelForm):
   class Meta:
       model = Act

Then your view:

from myapp.models import Act
from myapp.forms import ActForm


def add_view(request):
    if request.method == 'POST':
        form = ArticleForm(request.POST)
        if form.is_valid():
            form.save()
    else:
        form = ActForm() # Creating a empty form.
    return render_to_response("template.html", {
        "form": form,
    })

def edit_view(request):
    obj = Act.objects.get(pk=1)

    if request.method == 'POST':
        form = ArticleForm(request.POST)
        if form.is_valid():
            form.save()
    else:
        form = ActForm(instance=obj) # Creating form pre-filled with obj.
    return render_to_response("template.html", {
        "form": form,
    })

If you want to implement this situation more than once. DRY: https://docs.djangoproject.com/en/1.5/topics/class-based-views/intro/#handling-forms-with-class-based-views

In your template.html:

{{ form }}

Disclaimer: This code is not tested.
https://docs.djangoproject.com/en/1.5/ref/forms/
https://docs.djangoproject.com/en/1.5/topics/forms/modelforms/

Update:

You can pass multiple forms to one <form>...</form> in your template. So create two forms. One Act form (see above) and one GvtCompo formset. The formset contains all GvtCompo’s that have a relation to Act.

from django.forms.models import modelformset_factory

act = Act.objects.get(pk=1) #The same act as you used to create the form above.

GvtFormSet = modelformset_factory(GvtCompo)
formset = GvtFormSet(queryset=act.gvtCompo.all())

Template can be:

<form ...>
{% for field in form %}
    {% if field.name == "gvtCompo" %}
        {{ formset }}
    {% else %}
        {{ field }}
    {% endif %}
{% endfor %}
</form>

Note: If your form and formset have colliding field names use prefix=”some_prefix”:
Django – Working with multiple forms