Task: Schema-Matching (source dataset: prospect)

Task: 
Please identify the matching columns between Table A and Table B. For each column in Table A, specify the corresponding column in Table B. If a column in A has no corresponding column in Table B, you can map it to null. Represent each column mapping using a pair of column headers in a list, i.e., [Table A Column, Table B column or null]. Provide the mapping for each column in Table A and return all mappings in a list.

No explanation and return the matching columns in a structured JSON format: {"column_mappings": <a list of column pairs>}.

TableA:
| AgencyID   | Country               | LastName   | NumberChildren   | MiddleInitial   | Gender   | FirstName   | AddressLine1         | AddressLine2   | PostalCode   | City           | State                | Phone          |   Income |
|:-----------|:----------------------|:-----------|:-----------------|:----------------|:---------|:------------|:---------------------|:---------------|:-------------|:---------------|:---------------------|:---------------|---------:|
| PEL0       | hnitedStatesofAner7cz | P2LLAND    | 2.0              |                 | f        | Netti       | 21847 olympia street |                | T6b 1i1      | Fairbanks      | MA                   | 1-712-522-6088 |   368776 |
| LED1       | UnihedStatdsofAhe4ica | L4DUC      | 1.0              |                 | F        | TRUDY       | 245 congress court   | APT. 624       | 77281        | Quebec         | PA                   | 1-626-426-4298 |   177967 |
| lat2       | hnitevStateslfzmerica | layif      | 2.0              |                 |          | ireland     | 6517 frailing west   |                | 91355        | Henderson      | Alberta              | 1-524-787-8784 |   321772 |
| RUD3       | Canwda                | RUwDICK    | 5.0              |                 |          | Misti       | 11449 blalock park   |                | 36615        | Salem          | AR                   | 1-741-997-1688 |    25449 |
| JAY4       | Canafa                | JxYAMANNE  | 2.0              | M               | f        | sarena      | 18354 dodd court     | Apt. 619       | t6a 1i3      | Toledo         | OR                   | 1-002-194-1991 |   166567 |
| tod5       | 6nitedztatwsocAmerica | todo       | 2.0              | Z               | M        | Paulette    | 14117 roxboro street |                | A2b 1v3      | Corpus Christi | VA                   | 1-441-371-7651 |    43631 |
| Kan6       | Cansda                | manno      | 2.0              | R               | m        | AMALITA     | 24697 FLORENCE WEST  |                | 49513        | Salt Lake City | OH                   | 1-957-940-5980 |   466230 |
| Din7       | Un9t4dSta4esifAmerica | D8nkel     | 3.0              | Z               |          | Ernesto     | 6488 applewood drive |                | M5d 1v6      | Brownsville    | Prince Edward Island | 1-768-633-4096 |   420243 |
| Thi8       | UnitedSta4ds0fsmerica | Thigodeaud |                  |                 |          | Toby        | 17404 gale court     |                | V6c 1q1      | Escondido      | NV                   | 1-107-689-2155 |   141862 |
| May9       | Un7tedStatrsovwmerica | Mayo       | 0.0              |                 |          | evangelia   | 15913 alexis street  |                | 99716        | Los Angeles    | Ontario              | 1-173-594-6096 |   402011 |

TableB:
| gncd   | cntr                     | lstnm      | nmbrchldrn   | mddlntl   | gndr   | nmbrcrs   | mrtlstts   | g    | crdtrtng   | wnrrntflg   | mplr                     | nmbrcrdtcrds   |           ntwrth |
|:-------|:-------------------------|:-----------|:-------------|:----------|:-------|:----------|:-----------|:-----|:-----------|:------------|:-------------------------|:---------------|-----------------:|
| PEL0   | United States of America | PELLAND    | 3.0          |           | f      |           | W          | 20.0 | 760.0      | O           | Brink's                  |                |      1.05887e+06 |
| LED1   | United States of America | LEDUC      | 1.0          |           | F      | 5.0       | U          | 3.0  | 555.0      | U           |                          | 6.0            |      1.98818e+06 |
| lat2   | United States of America | latif      | 1.0          |           |        | 2.0       | S          |      | 566.0      | O           |                          | 6.0            |      3.67313e+06 |
| RUD3   | Canada                   | RUDDICK    | 1.0          |           |        | 2.0       | W          | 77.0 |            | O           | Air Products & Chemicals | 3.0            |      2.0059e+06  |
| JAY4   | Canada                   | JAYAMANNE  | 3.0          | M         | f      | 0.0       | M          | 21.0 | 815.0      | O           | Oshkosh                  | 4.0            | 624736           |
| tod5   | United States of America | todo       | 4.0          | Z         | M      | 1.0       | M          | 77.0 | 333.0      | R           |                          | 10.0           |      3.06462e+06 |
| Kan6   | Canada                   | Kanno      | 0.0          | R         | m      | 4.0       |            | 23.0 | 528.0      | O           | VeraSun Energy           | 1.0            |      3.48913e+06 |
| Din7   | United States of America | Dinkel     | 2.0          | Z         |        | 2.0       | M          | 9.0  | 680.0      | U           | IDT                      | 7.0            |      3.43074e+06 |
| Thi8   | United States of America | Thibodeaux |              |           |        | 3.0       | U          | 63.0 | 761.0      | O           | Adams Resources & Energy | 10.0           |      1.74361e+06 |
| May9   | United States of America | Mayo       | 2.0          |           |        | 0.0       | M          | 32.0 | 416.0      | O           | MGIC Investment          |                | 216299           |



source_headers: AgencyID
Country
LastName
NumberChildren
MiddleInitial
Gender
target_headers: gncd
cntr
lstnm
nmbrchldrn
mddlntl
gndr
column_mappings: AgencyID
gncd
Country
cntr
LastName
lstnm
NumberChildren
nmbrchldrn
MiddleInitial
mddlntl
Gender
gndr
output: {"column_mappings": [["AgencyID", "gncd"], ["Country", "cntr"], ["LastName", "lstnm"], ["NumberChildren", "nmbrchldrn"], ["MiddleInitial", "mddlntl"], ["Gender", "gndr"], ["FirstName", null], ["AddressLine1", null], ["AddressLine2", null], ["PostalCode", null], ["City", null], ["State", null], ["Phone", null], ["Income", null]]}