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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 page(self):
        '''Current page.'''
        page = self.request.GET.get(self.page_param)
        if not page:
            return 1
        try:
            page = int(page)
        except ValueError:
            self.invalid_page()
            return 1
        if page<1:
            self.invalid_page()
            return 1
        return page