提交表单时出错：'输入有效日期'

Question

my views.py：

def add_atten(request):
    if request.method == 'POST':
        form = AttendancenameForm(request.POST)
        if form.is_valid():
            form.save()
            return HttpResponseRedirect(reverse('student:listatten'))
        else:
            print(form.errors)
    else:       
         form = AttendancenameForm()
    return render(request, 'add_atten.html', {'form': form},)

我的template-add_atten.html：

{% if attendance %}
    <table>
        <tr>
            <th>Teacher</th>
            <th>Date</th>
            <th>IN-TIME</th>
            <th>OUT-TIME</th>
        </tr>
    {% for atten in attendance %}
        <tr>
            <td>{{atten.teacher_ name}}</td>
            <td>{{atten.date}}</td>
            <td>{{atten.intime}}</td>
            <td>{{atten.outtime}}</td>
            <td><a href="{% url 'student:updateatten' atten.id   %}">Update</a></td>
        <td><a href="{% url 'student:attendel' atten.pk %}">Delete</a></td>
    </tr>
{% endfor %}

my models.py:

class Attendancename(models.Model):
    teacher_name = models.ForeignKey(Teachername)
    date = models.DateField('Date')
    intime = models.TimeField('IN-TIME')
    outtime = models.TimeField('OUT-TIME')

my forms.py:

class AttendancenameForm(ModelForm):
    date = forms.DateField(input_formats=['%d-%m-%y'])
    intime = forms.TimeField(input_formats=['%H:%M'])
    outtime = forms.TimeField(input_formats=['%H:%M'])
    teacher_name = forms.ModelChoiceField(queryset=Teachername.objects.all())
    class Meta:
        model = Attendancename
        fields = ('teacher_name', 'date', 'intime', 'outtime',)

当我想提交日期值时，它会抛出错误'输入有效日期'。但是我总是提交有效值并尝试过不同的组合，但它不起作用。请建议我修复。

如果我从forms.py中省略'input_formats'并尝试使用django中的date字段的默认值提交我的表单中的值而不是显示任何错误，而不是上面的内容。请给我一个解决方案。