'Yields (page, page_url) from the given locations, skipping
locations that have errors.'

def _get_pages(self, locations, project_name):

    seen = set()
    for location in locations:
        if (location in seen):
            continue
        seen.add(location)
        page = self._get_page(location)
        if (page is None):
            continue
        (yield page)
