def new_workbookrels_text(db):
    """
    Returns /xl/_rels/workbook.xml.rels text

    :param pylightxl.Database db: database contains sheetnames, and their data
    :return str: /xl/_rels/workbook.xml.rels text
    """
    xml_base = (
        '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>\r\n<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">\r\n{many_tag_sheets}\r\n{tag_sharedStrings}\r\n</Relationships>'
        )
    xml_tag_sheet = (
        '<Relationship Target="worksheets/sheet{sheet_num}.xml" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/worksheet" Id="rId{sheet_num}"/>\r\n'
        )
    xml_tag_sharedStrings = (
        '<Relationship Target="sharedStrings.xml" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/sharedStrings" Id="rId{ID}"/>\r\n'
        )
    many_tag_sheets = ''
    for wsID, _ in enumerate(db.ws_names, 1):
        many_tag_sheets += xml_tag_sheet.format(sheet_num=wsID)
    if db._sharedStrings:
        tag_sharedStrings = xml_tag_sharedStrings.format(ID=len(db.ws_names
            ) + 1)
    else:
        tag_sharedStrings = ''
    rv = xml_base.format(many_tag_sheets=many_tag_sheets, tag_sharedStrings
        =tag_sharedStrings)
    return rv
