def _get_bib_element(bibitem, element):
    """Return element from bibitem or None."""
    lst = [i.strip() for i in bibitem.split("\n")]
    for i in lst:
        if i.startswith(element):
            value = i.split("=", 1)[-1]
            value = value.strip()
            while value.endswith(','):
                value = value[:-1]
            while value.startswith('{') or value.startswith('"'):
                value = value[1:-1]
            return value
    return None