如何允许输入既是从模型中选择的对象，又是django表单中的自由文本输入？

from django.db import models

class Category(models.Model):
    name = models.CharField(max_length=100)

    def __str__(self):
        return self.name

from django import forms

class InputForm(forms.Form):
    category = forms.ModelChoiceField(queryset=Category.objects.all())
    text_input = forms.CharField(max_length=100)

from django.shortcuts import render

def input_view(request):
    if request.method == 'POST':
        form = InputForm(request.POST)
        if form.is_valid():
            category = form.cleaned_data['category']
            text_input = form.cleaned_data['text_input']
            # 处理用户输入的逻辑
            # ...
    else:
        form = InputForm()
    
    return render(request, 'input.html', {'form': form})

<form method="post">
  {% csrf_token %}
  {{ form.as_p }}
  <button type="submit">提交</button>
</form>