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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 new_document(self):
 """ Creates a new, empty document in the remote and locally cached database, auto-generating the _id. :returns: Document instance corresponding to the new document in the database """

        doc = Document(self, None)
        doc.create()
        super(CouchDatabase, self).__setitem__(doc['_id'], doc)
        return doc