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what does parse_dates in report.py do with a date that has no timezone?

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fm code 'what does parse_dates in report.py do with a date that has no timezone?' --worker claude

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Answer

In report.py, parse_dates (lines 4-11) parses each row's r['when'] with datetime.fromisoformat (line 7). If the result has no tzinfo (line 8), it treats the value as UTC by calling d.replace(tzinfo=timezone.utc) (line 9). That attaches UTC without shifting the clock time. Every value, naive or aware, is then converted with astimezone(timezone.utc) (line 10) and appended to the returned list, so all outputs are UTC-aware datetimes.

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12s answer In report.py, parse_dates (lines 4-11) parses each row's r['when'] with datetime.fromisoformat (line 7). If the result has no tzinfo (line 8), it treats the value as UTC by calling d.replace(tzinfo=timezone.utc) (line 9). That attaches UTC without shifting the clock time. Every value, naive or aware, is then converted with astimezone(timezone.utc) (line 10) and appended to the returned list, so all outputs are UTC-aware datetimes.