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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 contains_no_backer(self, addr):
 """ Tests if the address is contained in any page of paged memory, without considering memory backers. :param int addr: The address to test. :return: True if the address is included in one of the pages, False otherwise. :rtype: bool """


        for i, p in self._pages.items():
            if i * self._page_size <= addr < (i + 1) * self._page_size:
                return addr - (i * self._page_size) in p.keys()
        return False