Task: Data-Imputation (source dataset: WebTable)

Please fill in the missing value in the input table. The missing value is denoted by '[MISSING]'. Please only return the value filled in. Do not return the whole table.

No explanation, return the value filled in JSON format: {"value": "filled_value"}. 

Input Table:
|   BR No. | SR No.    | Name                            | Built          | Rebuilt        | Withdrawn      | Preserved/location                                              | Preservation Status                                                                                                                                                                                                                       | Notes                                                                                                                                                      |
|---------:|:----------|:--------------------------------|:---------------|:---------------|:---------------|:----------------------------------------------------------------|:------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:-----------------------------------------------------------------------------------------------------------------------------------------------------------|
|    35001 | 21C1      | Channel Packet                  | February 1941  | August 1959    | November 1964  | nan                                                             | nan                                                                                                                                                                                                                                       | Entered SR service June 1941. Scrapped at Birds (Swansea) Ltd. 1965                                                                                        |
|    35002 | 21C2      | Union Castle                    | June 1941      | May 1958       | February 1964  | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at Slag Reduction Co. Ltd., Yorkshire 1964                                                                                                        |
|    35003 | 21C3      | Royal Mail                      | September 1941 | August 1959    | July 1967      | nan                                                             | nan                                                                                                                                                                                                                                       | Holder of class speed record (105.88 mph). Last authenticated 100 mph plus on British Railways by a steam locomotive. Scrapped at J Cashmore, Newport 1967 |
|    35004 | 21C4      | Cunard White Star               | October 1941   | July 1958      | October 1965   | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at Cohen's/Eastleigh Shed 1966                                                                                                                    |
|    35005 | 21C5      | Canadian Pacific                | December 1941  | May 1959       | October 1965   | Mid-Hants Railway                                               | Restored on the Great Central Railway at Loughborough and used on main line steam specials. Painted in British Railways Blue livery between 2000 and 2001. Now based at the Mid-Hants Railway. Currently under Overhaul in Eastleigh MPD. | nan                                                                                                                                                        |
|    35006 | 21C6      | Peninsular & Oriental S. N. Co. | December 1941  | October 1959   | August 1964    | Gloucestershire and Warwickshire Railway                        | Operational.                                                                                                                                                                                                                              | nan                                                                                                                                                        |
|    35007 | 21C7      | Aberdeen Commonwealth           | June 1942      | May 1958       | July 1967      | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at J. Buttigieg, Newport 1968                                                                                                                     |
|    35008 | 21C8      | Orient Line                     | June 1942      | May 1957       | July 1967      | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at J. Buttigieg, Newport 1968                                                                                                                     |
|    35009 | 21C9      | Shaw Savill                     | June 1942      | March 1957     | July 1964      | Private Site, Bury                                              | Stored awaiting restoration.                                                                                                                                                                                                              | nan                                                                                                                                                        |
|    35010 | 21C10     | Blue Star                       | July 1942      | January 1957   | September 1966 | Colne Valley Railway                                            | Stored                                                                                                                                                                                                                                    | nan                                                                                                                                                        |
|    35011 | 21C11     | General Steam Navigation        | December 1944  | July 1959      | February 1966  | Private Site, Sellindge, Kent (at RAF Binbrook until late 2007) | Under long-term restoration, and back-dating to Original condition.                                                                                                                                                                       | Regarded as the only British steam locomotive to bear the word 'steam' in the name; driving crank axle missing.                                            |
|    35012 | [MISSING] | United States Lines             | January 1945   | February 1957  | April 1967     | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at J Cashmore, Newport 1967                                                                                                                       |
|    35013 | 21C13     | Blue Funnel                     | February 1945  | May 1956       | July 1967      | nan                                                             | nan                                                                                                                                                                                                                                       | Originally named Blue Funnel Line, renamed Blue Funnel Certum Pete Finem on 21 June 1945. Scrapped at J. Buttigieg, Newport 1968                           |
|    35014 | 21C14     | Nederland Line                  | February 1945  | July 1956      | March 1967     | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at J Cashmore, Newport 1967                                                                                                                       |
|    35015 | 21C15     | Rotterdam Lloyd                 | March 1945     | June 1958      | February 1964  | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at Slag Reduction Co. Ltd., Yorkshire 1964                                                                                                        |
|    35016 | 21C16     | Elders Fyffes                   | March 1945     | April 1957     | August 1965    | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at Birds (Swansea) Ltd. 1965                                                                                                                      |
|    35017 | 21C17     | Belgian Marine                  | April 1945     | March 1957     | July 1966      | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at J. Buttigieg, Newport 1966                                                                                                                     |
|    35018 | 21C18     | British India Line              | May 1945       | February 1956  | August 1964    | WCRC Carnforth                                                  | Under restoration at Carnforth West Coast Railways to mainline standards                                                                                                                                                                  | Originally built with fabricated wheels that were replaced with conventional cast wheels in 1947                                                           |
|    35019 | 21C19     | French Line CGT                 | June 1945      | May 1959       | September 1965 | nan                                                             | nan                                                                                                                                                                                                                                       | The only member of the class to have script lettering on the nameplate, as used by French Line. Scrapped at J Cashmore, Newport 1966                       |
|    35020 | 21C20     | Bibby Line                      | June 1945      | April 1956     | February 1965  | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at BR/Eastleigh Works 1965                                                                                                                        |
|    35021 | -         | New Zealand Line                | September 1948 | June 1959      | August 1965    | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at Birds (Swansea) Ltd. 1965                                                                                                                      |
|    35022 | -         | Holland America Line            | October 1948   | June 1956      | May 1966       | Private Site, Bury                                              | Boiler overhauled for eventual use by 35027, awaiting restoration to mainline standards                                                                                                                                                   | nan                                                                                                                                                        |
|    35023 | -         | Holland-Afrika Line             | November 1948  | February 1957  | July 1967      | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at J. Buttigieg, Newport 1968                                                                                                                     |
|    35024 | -         | East Asiatic Company            | November 1948  | April 1959     | January 1965   | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at C. Woodfield and Sons, Newport 1965                                                                                                            |
|    35025 | -         | Brocklebank Line                | November 1948  | December 1956  | September 1964 | Private site at Sellindge, Kent                                 | Stored, pending long-term restoration                                                                                                                                                                                                     | nan                                                                                                                                                        |
|    35026 | -         | Lamport & Holt Line             | December 1948  | January 1957   | March 1967     | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at J Cashmore, Newport 1967                                                                                                                       |
|    35027 | -         | Port Line                       | December 1948  | May 1957       | September 1966 | Private Site, Bury                                              | Under overhaul. (see 35027 Port Line) Being restored to mainline standards, based at Southall                                                                                                                                             | nan                                                                                                                                                        |
|    35028 | -         | Clan Line                       | December 1948  | October 1959   | July 1967      | Stewarts Lane, London                                           | Operational, main-line certified                                                                                                                                                                                                          | nan                                                                                                                                                        |
|    35029 | -         | Ellerman Lines                  | February 1949  | September 1959 | September 1966 | National Railway Museum                                         | Sectioned Exhibit                                                                                                                                                                                                                         | nan                                                                                                                                                        |
|    35030 | -         | Elder Dempster Lines            | April 1949     | April 1958     | July 1967      | nan                                                             | nan                                                                                                                                                                                                                                       | Scrapped at J. Buttigieg, Newport 1968                                                                                                                     |



row_idx: 11
col_idx: 1
col_name: SR No.
label: 21C12