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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def save(self):
 """Save this entry. If the entry does not have an :attr:`id`, a new id will be assigned, and the :attr:`id` attribute set accordingly. Pre-save processing of the fields saved can be done by overriding the :meth:`prepare_save` method. Additional actions to be done after the save operation has been completed can be added by defining the :meth:`post_save` method. """

        id = self.id or self.objects.id(self.name)
        self.objects[id] = self.prepare_save(dict(self))
        self.id = id
        self.post_save()
        return id