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   | Employer                 | City           | NumberCreditCards   | Gender   | MiddleInitial   | LastName   | FirstName   | AddressLine1         | AddressLine2   | PostalCode   | State                | Country                  | Phone          |
|:-----------|:-------------------------|:---------------|:--------------------|:---------|:----------------|:-----------|:------------|:---------------------|:---------------|:-------------|:---------------------|:-------------------------|:---------------|
| PEL0       | Brink's                  | Fairbanks      |                     | f        |                 | PELLAND    | Netti       | 21847 olympia street |                | T6b 1i1      | MA                   | United States of America | 1-712-522-6088 |
| LED1       |                          | Quebec         | 6.0                 | F        |                 | LEDUC      | TRUDY       | 245 congress court   | APT. 624       | 77281        | PA                   | United States of America | 1-626-426-4298 |
| lat2       |                          | Henderson      | 6.0                 |          |                 | latif      | ireland     | 6517 frailing west   |                | 91355        | Alberta              | United States of America | 1-524-787-8784 |
| RUD3       | Air Products & Chemicals | Salem          | 3.0                 |          |                 | RUDDICK    | Misti       | 11449 blalock park   |                | 36615        | AR                   | Canada                   | 1-741-997-1688 |
| JAY4       | Oshkosh                  | Toledo         | 4.0                 | f        | M               | JAYAMANNE  | sarena      | 18354 dodd court     | Apt. 619       | t6a 1i3      | OR                   | Canada                   | 1-002-194-1991 |
| tod5       |                          | Corpus Christi | 10.0                | M        | Z               | todo       | Paulette    | 14117 roxboro street |                | A2b 1v3      | VA                   | United States of America | 1-441-371-7651 |
| Kan6       | VeraSun Energy           | Salt Lake City | 1.0                 | m        | R               | Kanno      | AMALITA     | 24697 FLORENCE WEST  |                | 49513        | OH                   | Canada                   | 1-957-940-5980 |
| Din7       | IDT                      | Brownsville    | 7.0                 |          | Z               | Dinkel     | Ernesto     | 6488 applewood drive |                | M5d 1v6      | Prince Edward Island | United States of America | 1-768-633-4096 |
| Thi8       | Adams Resources & Energy | Escondido      | 10.0                |          |                 | Thibodeaux | Toby        | 17404 gale court     |                | V6c 1q1      | NV                   | United States of America | 1-107-689-2155 |
| May9       | MGIC Investment          | Los Angeles    |                     |          |                 | Mayo       | evangelia   | 15913 alexis street  |                | 99716        | Ontario              | United States of America | 1-173-594-6096 |

TableB:
| AgencyID   | Employer                 | City           | NumberCreditCards   | Gender   | MiddleInitial   |   Income | NumberCars   | NumberChildren   | MaritalStatus   | Age   | CreditRating   | OwnOrRentFlag   |         NetWorth |
|:-----------|:-------------------------|:---------------|:--------------------|:---------|:----------------|---------:|:-------------|:-----------------|:----------------|:------|:---------------|:----------------|-----------------:|
| PEL0       | Brink's                  | Fairbanks      |                     | f        |                 |   368776 |              | 3.0              | W               | 20.0  | 760.0          | O               |      1.05887e+06 |
| LED1       |                          | Quebec         | 6.0                 | F        |                 |   177967 | 5.0          | 1.0              | U               | 3.0   | 555.0          | U               |      1.98818e+06 |
| lat2       |                          | Henderson      | 6.0                 |          |                 |   321772 | 2.0          | 1.0              | S               |       | 566.0          | O               |      3.67313e+06 |
| RUD3       | Air Products & Chemicals | Salem          | 3.0                 |          |                 |    25449 | 2.0          | 1.0              | W               | 77.0  |                | O               |      2.0059e+06  |
| JAY4       | Oshkosh                  | Toledo         | 4.0                 | f        | M               |   166567 | 0.0          | 3.0              | M               | 21.0  | 815.0          | O               | 624736           |
| tod5       |                          | Corpus Christi | 10.0                | M        | Z               |    43631 | 1.0          | 4.0              | M               | 77.0  | 333.0          | R               |      3.06462e+06 |
| Kan6       | VeraSun Energy           | Salt Lake City | 1.0                 | m        | R               |   466230 | 4.0          | 0.0              |                 | 23.0  | 528.0          | O               |      3.48913e+06 |
| Din7       | IDT                      | Brownsville    | 7.0                 |          | Z               |   420243 | 2.0          | 2.0              | M               | 9.0   | 680.0          | U               |      3.43074e+06 |
| Thi8       | Adams Resources & Energy | Escondido      | 10.0                |          |                 |   141862 | 3.0          |                  | U               | 63.0  | 761.0          | O               |      1.74361e+06 |
| May9       | MGIC Investment          | Los Angeles    |                     |          |                 |   402011 | 0.0          | 2.0              | M               | 32.0  | 416.0          | O               | 216299           |



source_headers: AgencyID
Employer
City
NumberCreditCards
Gender
MiddleInitial
target_headers: AgencyID
Employer
City
NumberCreditCards
Gender
MiddleInitial
column_mappings: AgencyID
AgencyID
Employer
Employer
City
City
NumberCreditCards
NumberCreditCards
Gender
Gender
MiddleInitial
MiddleInitial
output: {"column_mappings": [["AgencyID", "AgencyID"], ["Employer", "Employer"], ["City", "City"], ["NumberCreditCards", "NumberCreditCards"], ["Gender", "Gender"], ["MiddleInitial", "MiddleInitial"], ["LastName", null], ["FirstName", null], ["AddressLine1", null], ["AddressLine2", null], ["PostalCode", null], ["State", null], ["Country", null], ["Phone", null]]}