Django Import-Export：异常值：没有这样的列

Question

我的models.py

class Camco(models.Model):
    Customer_Name=models.CharField(max_length=200)
    Customer_No=models.CharField(max_length=200)

    def __unicode__(self):
        return self.Customer_Name

我的admin.py

    class CamcoResource(resources.ModelResource):
         class Meta:
            model=Camco
            fields = ('id', 'Customer_Name', 'Customer_No',)     
    class CamcoAdmin(ImportMixin,admin.ModelAdmin):
        recource_class = CamcoResource
        pass

    admin.site.register(Camco,CamcoAdmin)

错误

OperationalError at /admin/camco/camco/
no such column: camco_camco.Customer_No
Request Method: GET
Request URL:    http://localhost:53430/admin/camco/camco/
Django Version: 1.8.4
Exception Type: OperationalError
Exception Value:    
no such column: camco_camco.Customer_No
Exception Location: C:\Users\Administrator\Documents\Visual Studio 2013\Projects\agriscbeta\agriscbeta\env\lib\site-packages\django\db\backends\sqlite3\base.py in execute, line 318