如何在django中处理通过表单传递的空输入？

if 'input_field' in form.cleaned_data:
    input_value = form.cleaned_data['input_field']
    # 处理非空输入的逻辑
else:
    # 处理空输入的逻辑

from django.shortcuts import render
from .forms import MyForm

def my_view(request):
    if request.method == 'POST':
        form = MyForm(request.POST)
        if form.is_valid():
            if 'input_field' in form.cleaned_data:
                input_value = form.cleaned_data['input_field']
                # 处理非空输入的逻辑
            else:
                # 处理空输入的逻辑
                input_value = '默认值'
            # 其他处理逻辑
    else:
        form = MyForm()
    return render(request, 'my_template.html', {'form': form})