Task: Schema-Matching (source dataset: assays)

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:
|   assay_id | assay_subcellular_fraction   |   confidence_score | tissue_id   | variant_id   | relationship_type   |   doc_id | description                                                                                                 | assay_type   | assay_test_type   | assay_category   | assay_organism   | assay_tax_id   | assay_strain   |
|-----------:|:-----------------------------|-------------------:|:------------|:-------------|:--------------------|---------:|:------------------------------------------------------------------------------------------------------------|:-------------|:------------------|:-----------------|:-----------------|:---------------|:---------------|
|          1 |                              |                  8 |             |              | H                   |    11087 | The compound was tested for the in vitro inhibition of platelet 12-lipoxygenase at a concentration of 30 uM | B            |                   |                  |                  |                |                |
|          2 |                              |                  0 |             |              | U                   |      684 | Compound was evaluated for its ability to mobilize calcium in 1321NI cells                                  | F            |                   |                  |                  |                |                |
|          3 |                              |                  0 |             |              | U                   |    15453 |                                                                                                             | B            |                   |                  |                  |                |                |
|          4 |                              |                  4 |             |              | H                   |    17841 | Binding affinity against A2 adenosine receptor in bovine striatal membranes using [3H]CGS-21680             | B            |                   |                  | Bos taurus       | 9913.0         |                |
|          5 |                              |                  1 |             |              | N                   |    17430 | In vitro cell cytotoxicity against 143-B cell lines (Human osteosarcoma cell line)                          | F            |                   |                  | Homo sapiens     | 9606.0         |                |
|          6 |                              |                  1 |             |              | N                   |    17430 | In vitro cell cytotoxicity against 143-B cell lines (Human osteosarcoma cell line)                          | F            |                   |                  | Homo sapiens     | 9606.0         |                |
|          7 |                              |                  1 |             |              | N                   |    13799 | Cytotoxic Activity was evaluated against 143B (TK-) tumor cells                                             | F            |                   |                  | Mus musculus     | 10090.0        |                |
|          8 |                              |                  1 |             |              | N                   |    17774 | In vitro cell cytotoxicity was determined against 143B cell line                                            | F            |                   |                  | Homo sapiens     | 9606.0         |                |
|          9 |                              |                  1 |             |              | N                   |     3801 | Inhibitory activity against tumor osteosarcoma cell line 143B after 72 hr continuous exposure to compound   | F            |                   |                  | Homo sapiens     | 9606.0         |                |
|         10 |                              |                  1 |             |              | N                   |    17430 | In vitro cell cytotoxicity against 143B-LTK cell lines expressed in HSV-1 TK                                | F            |                   |                  | Homo sapiens     | 9606.0         |                |

TableB:
|   ss_d | ss_sbclllr_frctn   |   cnfdnc_scr | tss_d   | vrnt_d   | rltnshp_tp   | ss_tss   | ss_cll_tp   |     td | crtd_b       |   src_d | src_ss_d   | chmbl_d      | cll_d   | b_frmt      |
|-------:|:-------------------|-------------:|:--------|:---------|:-------------|:---------|:------------|-------:|:-------------|--------:|:-----------|:-------------|:--------|:------------|
|      1 |                    |            8 |         |          | H            |          |             |  12052 | Autocuration |       1 |            | CHEMBL615117 |         | BAO_0000019 |
|      2 |                    |            0 |         |          | U            |          |             |  22226 | Autocuration |       1 |            | CHEMBL615118 |         | BAO_0000219 |
|      3 |                    |            0 |         |          | U            |          |             |  22226 | Autocuration |       1 |            | CHEMBL615119 |         | BAO_0000019 |
|      4 |                    |            4 |         |          | H            |          |             | 104729 | Autocuration |       1 |            | CHEMBL615120 |         | BAO_0000249 |
|      5 |                    |            1 |         |          | N            |          | 143B        |  80001 | Intermediate |       1 |            | CHEMBL615121 | 163.0   | BAO_0000219 |
|      6 |                    |            1 |         |          | N            |          | 143B        |  80001 | Intermediate |       1 |            | CHEMBL615122 | 163.0   | BAO_0000219 |
|      7 |                    |            1 |         |          | N            |          | 143B        |  80001 | Intermediate |       1 |            | CHEMBL615123 | 163.0   | BAO_0000219 |
|      8 |                    |            1 |         |          | N            |          | 143B        |  80001 | Expert       |       1 |            | CHEMBL615124 | 163.0   | BAO_0000219 |
|      9 |                    |            1 |         |          | N            |          | 143B        |  80001 | Intermediate |       1 |            | CHEMBL615125 | 163.0   | BAO_0000219 |
|     10 |                    |            1 |         |          | N            |          | 143B        |  80001 | Intermediate |       1 |            | CHEMBL615126 | 163.0   | BAO_0000219 |



source_headers: assay_id
assay_subcellular_fraction
confidence_score
tissue_id
variant_id
relationship_type
target_headers: ss_d
ss_sbclllr_frctn
cnfdnc_scr
tss_d
vrnt_d
rltnshp_tp
column_mappings: assay_id
ss_d
assay_subcellular_fraction
ss_sbclllr_frctn
confidence_score
cnfdnc_scr
tissue_id
tss_d
variant_id
vrnt_d
relationship_type
rltnshp_tp
output: {"column_mappings": [["assay_id", "ss_d"], ["assay_subcellular_fraction", "ss_sbclllr_frctn"], ["confidence_score", "cnfdnc_scr"], ["tissue_id", "tss_d"], ["variant_id", "vrnt_d"], ["relationship_type", "rltnshp_tp"], ["doc_id", null], ["description", null], ["assay_type", null], ["assay_test_type", null], ["assay_category", null], ["assay_organism", null], ["assay_tax_id", null], ["assay_strain", null]]}