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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 _get_link_pages(page, per_page, count, page_url):
 # type: (int, int, int, str) -> Dict[str, str] """Create link header for page metadata. :param page: current page :param per_page: page limit :param count: count of all resources :param page_url: url for resources :return: dictionary with name of the link as key and its url as value """

    current_page = _page_arg(page)
    links = {}
    end = page * per_page

    if page > 1:
        links['prev'] = page_url.replace(current_page, _page_arg(page - 1))

    if end < count:
        links['next'] = page_url.replace(current_page, _page_arg(page + 1))

    if per_page < count:
        links['first'] = page_url.replace(current_page, _page_arg(1))
        links['last'] = page_url.replace(current_page, _page_arg((count + per_page - 1) // per_page))

    return links