from django.db import models


class Publisher(models.Model):
    name = models.CharField(max_length=100)

class Author(models.Model):
    name = models.CharField(max_length=100)

class Book(models.Model):
    name = models.CharField(max_length=100)
    authors = models.ManyToManyField(Author, related_name='books')
    publisher = models.ForeignKey(Publisher, related_name='books')