在django中，如何获取当前用户的用户名并将其分配给表单中的某个字段？

from django import forms

class MyForm(forms.Form):
    username_field = forms.CharField()

    def __init__(self, *args, **kwargs):
        current_username = kwargs.pop('current_username', None)
        super().__init__(*args, **kwargs)
        if current_username:
            self.fields['username_field'].initial = current_username

from django.shortcuts import render
from .forms import MyForm

def my_view(request):
    form = MyForm(current_username=request.user.username)
    return render(request, 'my_template.html', {'form': form})

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