def str_is_well_formed(xml_str):
    """
  Args:
    xml_str : str
      DataONE API XML doc.

  Returns:
    bool: **True** if XML doc is well formed.
  """
    try:
        str_to_etree(xml_str)
    except xml.etree.ElementTree.ParseError:
        return False
    else:
        return True