我目前在尝试将CSV文件上传到Django Heroku CRM应用程序时遇到这个错误，该应用程序也使用Heroku Postgres DB：

Unable to upload file. ValidationError(['“” value has an invalid date format. It must be in YYYY-MM-DD format.'])
&
Unable to upload file. ValidationError(['“1995-03-28” value has an invalid date format. It must be in YYYY-MM-DD format.'])

下面是我目前使用的代码块：

- views.py

class LeadImportView(LoginRequiredMixin, FormView):
    form_class = LeadImportForm
    template_name = 'import_leads.html'
    success_url = '/dashboard/leads/'
    def form_valid(self, form):
            df = pd.read_csv(io.StringIO(csv_file.read().decode('utf-8')))
            for index, row in df.iterrows():
                lead = Lead()
                ...
                dob = row['DOB']
                if str(dob).strip() == 'nan' or str(dob).strip() == "":
                    try:
                        lead.dob = None
                    except ValidationError:
                        lead.dob = None
                else:
                    lead.dob = dob
                ...
                lead.save()
            
            messages.success(self.request, 'Leads successfully imported.')
            # return redirect('leads:lead-list')
            return super().form_valid(form)

 - forms.py

class LeadForm(forms.Form):
    ...
    dob = forms.DateField()
    ...

 - models.py

class Lead(models.Model):
    ...
    dob = models.DateField(max_length=10, blank=True, null=True)
    ...

正如您所看到的，如果CSV dob值为空，那么它应该等于DB中的None值。然而，无论DOB是否被适当地填充或为空，代码仍然出错。任何见解都有帮助。此外，我更希望日期格式是MM/DD/YYYY，但我不完全确定如何覆盖djangos默认%Y%m%d