def _put_pages(self):
        """ First, the Document object does the heavy-lifting for the
            individual page objects and content.

            Then, the overall "Pages" object is generated.

        """
        self.document._get_orientation_changes()
        self.document._output_pages()

        # Pages Object, provides reference to page objects (Kids list).
        self.session._add_object(1)
        self.session._out('<</Type /Pages')
        kids = '/Kids ['
        for i in xrange(0, len(self.document.pages)):
            kids += str(3 + 2 * i) + ' 0 R '
        self.session._out(kids + ']')
        self.session._out('/Count %s' % len(self.document.pages))

        # Overall size of the default PDF page
        self.session._out('/MediaBox [0 0 %.2f %.2f]' %
                          (self.document.page.width,
                           self.document.page.height))
        self.session._out('>>')
        self.session._out('endobj')
First, the Document object does the heavy-lifting for the
            individual page objects and content.

            Then, the overall "Pages" object is generated.