TypeError in TinyPersonFactory when LOGLEVEL=INFO/DEBUG: set is not JSON serializable

[takechanman1228]

Summary

TinyPersonFactory.create_factory_from_demography() raises a TypeError when logging level is set to INFO or DEBUG in config.ini. The error occurs in debug logging code that attempts to serialize self.sampling_dimensions using json.dumps(), but the dictionary contains Python set objects which are not JSON serializable.

This issue does not occur when LOGLEVEL=ERROR (the default), but users who enable more verbose logging for debugging purposes encounter this crash.

Error Traceback

TypeError: Object of type set is not JSON serializable

File ~/TinyTroupe/tinytroupe/factory/tiny_person_factory.py, line 532, in _initialize_sampling_plan_transaction
    logger.debug(f"Sampling dimensions: {json.dumps(self.sampling_dimensions, indent=4)}")

File ~/miniconda3/lib/python3.12/json/encoder.py, line 180, in default
    raise TypeError(f'Object of type {o.__class__.__name__} '
                    f'is not JSON serializable')

Root Cause

File: tinytroupe/factory/tiny_person_factory.py
Line: 532

self.sampling_dimensions = utils.try_function(lambda: self._compute_sampling_dimensions(...))
logger.info("Sampling dimensions computed successfully.")
logger.debug(f"Sampling dimensions: {json.dumps(self.sampling_dimensions, indent=4)}")  # ← CRASHES HERE

Problem:

• self.sampling_dimensions contains Python set objects (likely used for deduplication)
• json.dumps() cannot serialize set type by default
• This logging statement only executes when LOGLEVEL=DEBUG