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 FILE HANDLING — LOG FILE ANALYZER - Demo Run
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Generated sample log: sample.log

--- Reading and displaying first 5 lines ---
  2026-01-15 08:00:00 [INFO] Server started
  2026-01-15 08:03:00 [WARNING] High memory usage
  2026-01-15 08:06:00 [INFO] Server started
  2026-01-15 08:09:00 [INFO] Server started
  2026-01-15 08:12:00 [INFO] Server started

--- Log level counts ---
  INFO: 21
  WARNING: 8
  ERROR: 1

--- Extracted ERROR lines ---
  2026-01-15 08:39:00 [ERROR] Database unreachable

Wrote 1 error lines to errors_only.log

--- Appending a new entry ---
  Last line in log after append: 2026-09-06 16:54:54 [INFO] Manual log entry added

--- Missing file handling ---
  safe_read_log('nonexistent.log') = None

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 Assignment: summarize_log
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  Level counts: {'INFO': 22, 'WARNING': 8, 'ERROR': 1}
  Earliest: 2026-01-15 08:00:00
  Latest: 2026-09-06 16:54:54
  3 most recent errors:
    2026-01-15 08:39:00 [ERROR] Database unreachable
