def split_tagstring(s, uni_key=False, has_pos=False):
    """
    Returns attribute-value mapping from UD-type CONLL field
    @param uni_key: if toggled, returns attribute-value pairs as joined strings (with the '=')
    """
    if has_pos:
        s = s.split('\t')[1]
    ret = [] if uni_key else {}
    if '=' not in s:
        return ret
    for attval in s.split('|'):
        attval = attval.strip()
        if not uni_key:
            a, v = attval.split('=')
            ret[a] = v
        else:
            ret.append(attval)
    return ret
