Python-сообщество

# -*- coding: utf-8 -
from django.db import models

class sensor_type(models.Model):
    measuring = models.CharField(max_length=30)#измеряемая величина
    unit = models.CharField(max_length=30)#единица измерения
    def __unicode__(self):
        return self.measuring
    class Meta:
        ordering = ["measuring"]
    class Admin:
        pass


class measuring_datetime(models.Model):
    datetime = models.DateTimeField(null=False)
    def __unicode__(self):
       return str(self.datetime)
    class Meta:
        ordering = ["datetime"]
    class Admin:
        pass


class measuring_value(models.Model):
    datetime = models.ForeignKey(measuring_datetime, null=False)
    sensor = models.ForeignKey(sensor_type, null=False)    
    value = models.FloatField(null=False)   
    def __unicode__(self):
       return str(self.value)
    class Meta:
        ordering = ["value"]
    class Admin:
        pass