如何传递向ManyToMany存储提交ModelForm的用户的信息？

from django.shortcuts import render
from .models import User, Group
from .forms import UserForm

def submit_form(request):
    if request.method == 'POST':
        form = UserForm(request.POST)
        if form.is_valid():
            user = form.save(commit=False)  # 创建保存点，暂时不保存到数据库
            user.save()  # 保存用户对象到数据库
            groups = form.cleaned_data['groups']  # 获取提交的 ManyToMany 数据

            # 处理 ManyToMany 数据
            for group_id in groups:
                group = Group.objects.get(id=group_id)
                user.groups.add(group)  # 添加到 ManyToMany 关系中

            return render(request, 'success.html')
    else:
        form = UserForm()
    
    return render(request, 'form.html', {'form': form})