Generated Model Artifacts

FABLE Pyculator is a wrapper and notebook interface for Modelwright-generated Python models. It does not currently generate those models from a FABLE workbook.

That boundary matters when comparing workbook versions. The 2021 workbook should be paired with a 2021 generated Python model. Running a 2021 workbook-derived wrapper against the 2020 generated model can produce plausible-looking tables with the wrong calculation artifact behind them.

Local Artifact Contract

Keep generated models under ignored tmp/ paths:

Workbook version	Source workbook	Matching generated model
2020	`tmp/private-workbooks/2020_Open_FABLECalculator.xlsx`	`tmp/generated-models/fable-2020/generated_fable_2020_model.py`
2021	`tmp/private-workbooks/2021_Open_FABLECalculator.xlsx`	`tmp/generated-models/fable-2021/generated_fable_2021_model.py`

The 2020 example notebook may materialize the compressed 2020 generated model from a sibling Modelwright checkout. The 2021 example notebook materializes the validated compressed 2021 generated model tracked in this repository:

examples/fable_2021/generated_fable_2021_model.py.xz

That archive is the only tracked generated-model exception in this repository. Source workbooks, decompressed generated models, raw generation JSON files, and validation reports still belong under ignored tmp/ paths.

To prepare or explicitly run a local 2021 rebuild from the public source workbook, see FABLE FreshForge Rebuild Command. To compare output-ref boundaries before choosing a rebuild target, see Output-Ref Strategy Comparison. To package compact evidence across an explicit output-ref strategy matrix run, see FABLE 2021 Benchmark Matrix Evidence Cookbook.

Spec Discovery Versus Model Generation

The notebook spec helpers discover FABLE-C wrapper metadata:

from fable_pyculator import build_2021_notebook_spec

spec = build_2021_notebook_spec("tmp/private-workbooks/2021_Open_FABLECalculator.xlsx")

This reads workbook structure such as scenario selection controls, scenario-definition tables, output tables, and curated headline series. It does not produce generated calculation source.

The run helpers load an already-generated Python model:

from fable_pyculator import run_2021_notebook_loop

result = run_2021_notebook_loop(
    {"gdp_scen": "SSP1"},
    workbook_path="tmp/private-workbooks/2021_Open_FABLECalculator.xlsx",
    generated_model_path="tmp/generated-models/fable-2021/generated_fable_2021_model.py",
    include_figures=False,
)

If the generated model path is missing, restore or create that artifact first. Do not point the 2021 helper at tmp/generated-models/fable-2020/generated_fable_2020_model.py.

About Modelwright JSON Inputs

Modelwright’s low-level generation command expects explicit JSON artifacts:

contract.json describes the generated module boundary: selected inputs, selected outputs, generated symbols, and dependency scope.
expressions.json contains translated formula expressions for generated symbols.
constants.json contains literal input values or cached constants needed by the generated model.

Those files are Modelwright generation inputs. FABLE Pyculator does not currently expose an API that creates them from a FABLE workbook, and it should not silently invent them. The 2021 generated model published here was created by Modelwright during Phase 8 and then compressed for notebook users.

Current Validation Boundary

The 2020 generated model tracked in the sibling Modelwright repository has Modelwright validation evidence. Phase 8 added matching FABLE Pyculator evidence for the public 2021 FABLE-C generated model artifact:

extracted sheets: 62;
extracted cells: 413,776;
formula cells: 297,002;
translated formula cells: 297,002;
comparable cached outputs: 281,922;
generated-output matches: 281,922;
mismatches: 0;
non-comparable cached blank formula outputs: 15,080.

The 2021 claim is limited to the public 2021 FABLE-C workbook and the compressed generated model artifact in examples/fable_2021/. It is not a claim about arbitrary country calculators, production readiness, or FABLE-P Canada equivalence.

Compact Evidence Summaries

After running a local Modelwright/FreshForge generated-model workflow, use scripts/package_fable_validation_evidence.py to summarize restored artifacts under tmp/generated-models/fable-YYYY/. The command writes compact summaries under tmp/validation-evidence/fable-YYYY/ and reports incomplete evidence unless explicit comparison counts are present. See Validation Evidence Packaging.

For manual benchmark orchestration around those artifacts, including extraction-only, FreshForge plan, and explicit FreshForge run modes, use Opt-In Benchmark Evidence Workflow.