The certificate of authority of a surety insurer, issued as provided under this code, shall be evidence of the authority of the insurer to become and to be accepted as sole surety on all private bonds and contracts, and on all bonds, undertakings, recognizances and obligations required or permitted by law or the charter, ordinances, rules or regulations of any municipality, board, body, organization or public officer and of the solvency and credit of such insurer for all authorized purposes and its sufficiency as such surety.