def get_page_content(page_ann, base_text):
    """Return page content from base text

    Args:
        page_ann (dict): span of page, page reference, page index are included
        base_text (str): base text

    Returns:
        str: page content
    """
    page_span = page_ann["span"]
    page_start_idx = page_span["start"]
    page_end_idx = page_span["end"]
    page_content = base_text[page_start_idx : page_end_idx + 1]
    return page_content