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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 iter(self, pages=None):
        '''Get an iterator of pages.

        :param int pages: optional limit to number of pages
        :return: iter of this and subsequent pages
        '''
        i = self._pages()
        if pages is not None:
            i = itertools.islice(i, pages)
        return i