class Articles(models.Model):
    create_date=models.DateTimeField(auto_now=True)
    name=models.CharField("Название статьи",max_length=200)
    text=models.TextField(verbose_name="Текст")
class Files(models.Model):
    aticle=models.ForeignKey(Article,on_delete=models.CASCADE,related_name='files_articles')
    file=models.FileField(upload_to='files/')

 def user_directory_path(instance, filename):
    # file will be uploaded to MEDIA_ROOT/user_<id>/<filename>
    return 'user_{0}/{1}'.format(instance.user.id, filename)
class MyModel(models.Model):
    upload = models.FileField(upload_to=user_directory_path)

 upload_to='uploads/%Y/%m/%d/'