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FA-67196 / Railway interlocking logic / Open access

Signal replacement and stick control: danger on occupancy · case 01

A signal clears into a section that is already occupied.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The occupancy test only replaces a clear signal; a danger signal can then clear over the occupied section.

THE FAILURE

The occupancy test only replaces a clear signal; a danger signal can then clear over the occupied section.

Unsuccessful approach: Exempting automatic signals lets them clear into an occupied block.

Case contract

Each step gives [section beyond occupied, route set, approach occupied]. An auto signal behaves as permanently routed. A signal shows danger whenever the section beyond is occupied; a signal that was clear when a train occupies that section latches a stick that keeps it at danger until the route is set afresh (off then on); auto signals drop the stick every step. Otherwise it clears when routed, not stuck, and for approach-released signals only with the approach occupied. Output the state per step.

Why this case matters

Interlocking logic decides whether trains may be given authority; a wrong decision at this point either grants unsafe movements or strands traffic.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    mode = x['mode']
    state = 'danger'
    stick = False
    prev_route = False
    out = []
    for occ, route, appr in x['steps']:
        if mode == 'auto':
            route = True
        if (route and not prev_route) or mode == 'auto':
            stick = False
        if occ and state == 'clear':
            if state == 'clear':
                stick = True
            state = 'danger'
        elif route and not stick and (mode != 'approach' or appr):
            state = 'clear'
        else:
            state = 'danger'
        prev_route = route
        out.append(state)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: occupied before clearing', {'mode': 'auto', 'steps': [[True, False, False], [True, False, False], [False, False, False]]}, ['danger', 'danger', 'clear']), ('boundary: automatic signal re-clears', {'mode': 'auto', 'steps': [[False, False, False], [True, False, True], [False, False, False]]}, ['clear', 'danger', 'clear']), ('sampled regression 12', {'mode': 'controlled', 'steps': [[False, False, True], [False, True, True], [True, False, True], [False, False, False], [False, False, True], [True, True, True], [True, False, False]]}, ['danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger']), ('boundary: second train behind on the same route', {'mode': 'controlled', 'steps': [[False, True, True], [True, True, True], [False, True, True]]}, ['clear', 'danger', 'danger']), ('boundary: route re-set after a train', {'mode': 'controlled', 'steps': [[False, True, True], [True, True, True], [False, False, True], [False, True, True]]}, ['clear', 'danger', 'danger', 'clear']), ('control 1', {'mode': 'auto', 'steps': [[False, True, False], [False, False, True], [False, True, False], [False, False, True], [False, False, False]]}, ['clear', 'clear', 'clear', 'clear', 'clear']), ('control 4', {'mode': 'controlled', 'steps': [[False, False, False], [False, True, True], [True, True, True], [False, True, True], [False, False, False]]}, ['danger', 'clear', 'danger', 'danger', 'danger']), ('control 7', {'mode': 'approach', 'steps': [[False, False, False], [False, False, False], [False, False, True], [False, False, True], [False, True, False], [False, False, True], [False, True, True], [False, True, True], [False, True, True], [True, True, True]]}, ['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear', 'clear', 'clear', 'danger'])], [('regression: controlled signal with a standing train', {'mode': 'controlled', 'steps': [[True, True, True], [False, True, True]]}, ['danger', 'clear']), ('regression: occupied before clearing', {'mode': 'auto', 'steps': [[True, False, False], [True, False, False], [False, False, False]]}, ['danger', 'danger', 'clear']), ('sampled regression 31', {'mode': 'auto', 'steps': [[False, True, False], [False, True, False], [False, True, False], [False, True, True], [False, True, False], [False, True, False], [True, True, False], [True, False, True], [True, False, True]]}, ['clear', 'clear', 'clear', 'clear', 'clear', 'clear', 'danger', 'danger', 'danger']), ('boundary: approach-released signal with empty approach', {'mode': 'approach', 'steps': [[False, True, False], [False, True, True]]}, ['danger', 'clear']), ('boundary: approach-released signal replaced by train', {'mode': 'approach', 'steps': [[False, True, True], [True, True, True], [False, True, True]]}, ['clear', 'danger', 'danger']), ('sampled regression 12', {'mode': 'controlled', 'steps': [[False, False, True], [False, True, True], [True, False, True], [False, False, False], [False, False, True], [True, True, True], [True, False, False]]}, ['danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger']), ('control 15', {'mode': 'approach', 'steps': [[False, True, True], [False, True, False], [False, True, True]]}, ['clear', 'danger', 'clear']), ('sampled regression 18', {'mode': 'approach', 'steps': [[False, True, False], [False, False, False], [False, False, False], [True, True, False], [False, True, False], [True, True, True], [False, True, True]]}, ['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear'])], [('regression: occupied before clearing', {'mode': 'auto', 'steps': [[True, False, False], [True, False, False], [False, False, False]]}, ['danger', 'danger', 'clear']), ('boundary: automatic signal re-clears', {'mode': 'auto', 'steps': [[False, False, False], [True, False, True], [False, False, False]]}, ['clear', 'danger', 'clear']), ('sampled regression 51', {'mode': 'controlled', 'steps': [[False, False, True], [False, False, False], [False, True, False], [False, True, True], [True, False, True], [False, False, True], [True, True, False]]}, ['danger', 'danger', 'clear', 'clear', 'danger', 'danger', 'danger']), ('sampled regression 54', {'mode': 'auto', 'steps': [[True, True, False], [False, True, False], [False, False, True], [False, False, True], [False, False, True], [False, True, True], [True, True, True], [False, True, False], [False, True, True], [False, True, False]]}, ['danger', 'clear', 'clear', 'clear', 'clear', 'clear', 'danger', 'clear', 'clear', 'clear']), ('regression: controlled signal with a standing train', {'mode': 'controlled', 'steps': [[True, True, True], [False, True, True]]}, ['danger', 'clear']), ('control 23', {'mode': 'controlled', 'steps': [[False, True, True], [False, True, False], [False, True, True], [True, True, False], [False, True, False]]}, ['clear', 'clear', 'clear', 'danger', 'danger']), ('control 26', {'mode': 'approach', 'steps': [[False, False, False], [False, True, True], [True, True, False], [True, False, True], [True, True, False], [True, False, True], [False, False, False], [False, True, True], [False, False, True], [False, True, False]]}, ['danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear', 'danger', 'danger']), ('sampled regression 29', {'mode': 'auto', 'steps': [[True, False, False], [False, False, False], [True, False, False], [False, False, True], [False, False, False], [False, True, True], [False, True, True], [False, False, False], [True, False, True], [False, True, False]]}, ['danger', 'clear', 'danger', 'clear', 'clear', 'clear', 'clear', 'clear', 'danger', 'clear'])], [('regression: controlled signal with a standing train', {'mode': 'controlled', 'steps': [[True, True, True], [False, True, True]]}, ['danger', 'clear']), ('regression: occupied before clearing', {'mode': 'auto', 'steps': [[True, False, False], [True, False, False], [False, False, False]]}, ['danger', 'danger', 'clear']), ('sampled regression 71', {'mode': 'approach', 'steps': [[False, True, False], [True, True, True], [False, True, True], [False, True, True], [True, True, True], [False, True, False]]}, ['danger', 'danger', 'clear', 'clear', 'danger', 'danger']), ('control 69', {'mode': 'auto', 'steps': [[False, False, False], [False, True, False], [False, True, False], [False, False, False], [False, False, True], [True, False, False], [False, False, True], [False, False, True], [False, False, False]]}, ['clear', 'clear', 'clear', 'clear', 'clear', 'danger', 'clear', 'clear', 'clear']), ('boundary: second train behind on the same route', {'mode': 'controlled', 'steps': [[False, True, True], [True, True, True], [False, True, True]]}, ['clear', 'danger', 'danger']), ('control 34', {'mode': 'approach', 'steps': [[False, True, True], [False, False, False], [False, True, True], [False, False, False], [True, False, True], [False, False, True], [True, False, False], [True, False, True]]}, ['clear', 'danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger']), ('control 37', {'mode': 'approach', 'steps': [[False, False, True], [True, False, False], [False, False, True], [False, False, True], [True, False, True], [False, False, False], [False, False, True], [False, False, True], [False, False, False]]}, ['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'danger']), ('sampled regression 40', {'mode': 'auto', 'steps': [[False, True, True], [True, True, True], [False, True, True], [False, True, False], [True, False, True], [True, False, True], [True, False, True]]}, ['clear', 'danger', 'clear', 'clear', 'danger', 'danger', 'danger'])], [('regression: occupied before clearing', {'mode': 'auto', 'steps': [[True, False, False], [True, False, False], [False, False, False]]}, ['danger', 'danger', 'clear']), ('boundary: automatic signal re-clears', {'mode': 'auto', 'steps': [[False, False, False], [True, False, True], [False, False, False]]}, ['clear', 'danger', 'clear']), ('sampled regression 79', {'mode': 'auto', 'steps': [[False, True, False], [True, True, False], [True, True, False]]}, ['clear', 'danger', 'danger']), ('boundary: route re-set after a train', {'mode': 'controlled', 'steps': [[False, True, True], [True, True, True], [False, False, True], [False, True, True]]}, ['clear', 'danger', 'danger', 'clear']), ('boundary: approach-released signal with empty approach', {'mode': 'approach', 'steps': [[False, True, False], [False, True, True]]}, ['danger', 'clear']), ('control 45', {'mode': 'approach', 'steps': [[False, False, False], [False, False, False], [False, True, False], [False, True, False], [True, True, False], [False, True, False], [False, True, False], [False, True, True]]}, ['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear']), ('control 48', {'mode': 'approach', 'steps': [[True, True, False], [False, True, True], [False, False, False], [False, False, True], [False, True, True], [True, True, False]]}, ['danger', 'clear', 'danger', 'danger', 'clear', 'danger']), ('sampled regression 51', {'mode': 'controlled', 'steps': [[False, False, True], [False, False, False], [False, True, False], [False, True, True], [True, False, True], [False, False, True], [True, True, False]]}, ['danger', 'danger', 'clear', 'clear', 'danger', 'danger', 'danger'])]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: occupied before clearing['clear', 'danger', 'clear']['danger', 'danger', 'clear']Failed
boundary: automatic signal re-clears['clear', 'danger', 'clear']['clear', 'danger', 'clear']Passed
sampled regression 12['danger', 'clear', 'danger', 'danger', 'danger', 'clear', 'danger']['danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger']Failed
boundary: second train behind on the same route['clear', 'danger', 'danger']['clear', 'danger', 'danger']Passed
boundary: route re-set after a train['clear', 'danger', 'danger', 'clear']['clear', 'danger', 'danger', 'clear']Passed
control 1['clear', 'clear', 'clear', 'clear', 'clear']['clear', 'clear', 'clear', 'clear', 'clear']Passed
control 4['danger', 'clear', 'danger', 'danger', 'danger']['danger', 'clear', 'danger', 'danger', 'danger']Passed
control 7['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear', 'clear', 'clear', 'danger']['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear', 'clear', 'clear', 'danger']Passed

SHA-256 / 9dcaa46dacd4224d2305bd1f13eea058e25b4f2d607133172967cd3551bbdcaa

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    mode = x['mode']
    state = 'danger'
    stick = False
    prev_route = False
    out = []
    for occ, route, appr in x['steps']:
        if mode == 'auto':
            route = True
        if (route and not prev_route) or mode == 'auto':
            stick = False
        if occ and mode != 'auto':
            if state == 'clear':
                stick = True
            state = 'danger'
        elif route and not stick and (mode != 'approach' or appr):
            state = 'clear'
        else:
            state = 'danger'
        prev_route = route
        out.append(state)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: occupied before clearing', {'mode': 'auto', 'steps': [[True, False, False], [True, False, False], [False, False, False]]}, ['danger', 'danger', 'clear']), ('boundary: automatic signal re-clears', {'mode': 'auto', 'steps': [[False, False, False], [True, False, True], [False, False, False]]}, ['clear', 'danger', 'clear']), ('sampled regression 12', {'mode': 'controlled', 'steps': [[False, False, True], [False, True, True], [True, False, True], [False, False, False], [False, False, True], [True, True, True], [True, False, False]]}, ['danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger']), ('boundary: second train behind on the same route', {'mode': 'controlled', 'steps': [[False, True, True], [True, True, True], [False, True, True]]}, ['clear', 'danger', 'danger']), ('boundary: route re-set after a train', {'mode': 'controlled', 'steps': [[False, True, True], [True, True, True], [False, False, True], [False, True, True]]}, ['clear', 'danger', 'danger', 'clear']), ('control 1', {'mode': 'auto', 'steps': [[False, True, False], [False, False, True], [False, True, False], [False, False, True], [False, False, False]]}, ['clear', 'clear', 'clear', 'clear', 'clear']), ('control 4', {'mode': 'controlled', 'steps': [[False, False, False], [False, True, True], [True, True, True], [False, True, True], [False, False, False]]}, ['danger', 'clear', 'danger', 'danger', 'danger']), ('control 7', {'mode': 'approach', 'steps': [[False, False, False], [False, False, False], [False, False, True], [False, False, True], [False, True, False], [False, False, True], [False, True, True], [False, True, True], [False, True, True], [True, True, True]]}, ['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear', 'clear', 'clear', 'danger'])], [('regression: controlled signal with a standing train', {'mode': 'controlled', 'steps': [[True, True, True], [False, True, True]]}, ['danger', 'clear']), ('regression: occupied before clearing', {'mode': 'auto', 'steps': [[True, False, False], [True, False, False], [False, False, False]]}, ['danger', 'danger', 'clear']), ('sampled regression 31', {'mode': 'auto', 'steps': [[False, True, False], [False, True, False], [False, True, False], [False, True, True], [False, True, False], [False, True, False], [True, True, False], [True, False, True], [True, False, True]]}, ['clear', 'clear', 'clear', 'clear', 'clear', 'clear', 'danger', 'danger', 'danger']), ('boundary: approach-released signal with empty approach', {'mode': 'approach', 'steps': [[False, True, False], [False, True, True]]}, ['danger', 'clear']), ('boundary: approach-released signal replaced by train', {'mode': 'approach', 'steps': [[False, True, True], [True, True, True], [False, True, True]]}, ['clear', 'danger', 'danger']), ('sampled regression 12', {'mode': 'controlled', 'steps': [[False, False, True], [False, True, True], [True, False, True], [False, False, False], [False, False, True], [True, True, True], [True, False, False]]}, ['danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger']), ('control 15', {'mode': 'approach', 'steps': [[False, True, True], [False, True, False], [False, True, True]]}, ['clear', 'danger', 'clear']), ('sampled regression 18', {'mode': 'approach', 'steps': [[False, True, False], [False, False, False], [False, False, False], [True, True, False], [False, True, False], [True, True, True], [False, True, True]]}, ['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear'])], [('regression: occupied before clearing', {'mode': 'auto', 'steps': [[True, False, False], [True, False, False], [False, False, False]]}, ['danger', 'danger', 'clear']), ('boundary: automatic signal re-clears', {'mode': 'auto', 'steps': [[False, False, False], [True, False, True], [False, False, False]]}, ['clear', 'danger', 'clear']), ('sampled regression 51', {'mode': 'controlled', 'steps': [[False, False, True], [False, False, False], [False, True, False], [False, True, True], [True, False, True], [False, False, True], [True, True, False]]}, ['danger', 'danger', 'clear', 'clear', 'danger', 'danger', 'danger']), ('sampled regression 54', {'mode': 'auto', 'steps': [[True, True, False], [False, True, False], [False, False, True], [False, False, True], [False, False, True], [False, True, True], [True, True, True], [False, True, False], [False, True, True], [False, True, False]]}, ['danger', 'clear', 'clear', 'clear', 'clear', 'clear', 'danger', 'clear', 'clear', 'clear']), ('regression: controlled signal with a standing train', {'mode': 'controlled', 'steps': [[True, True, True], [False, True, True]]}, ['danger', 'clear']), ('control 23', {'mode': 'controlled', 'steps': [[False, True, True], [False, True, False], [False, True, True], [True, True, False], [False, True, False]]}, ['clear', 'clear', 'clear', 'danger', 'danger']), ('control 26', {'mode': 'approach', 'steps': [[False, False, False], [False, True, True], [True, True, False], [True, False, True], [True, True, False], [True, False, True], [False, False, False], [False, True, True], [False, False, True], [False, True, False]]}, ['danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear', 'danger', 'danger']), ('sampled regression 29', {'mode': 'auto', 'steps': [[True, False, False], [False, False, False], [True, False, False], [False, False, True], [False, False, False], [False, True, True], [False, True, True], [False, False, False], [True, False, True], [False, True, False]]}, ['danger', 'clear', 'danger', 'clear', 'clear', 'clear', 'clear', 'clear', 'danger', 'clear'])], [('regression: controlled signal with a standing train', {'mode': 'controlled', 'steps': [[True, True, True], [False, True, True]]}, ['danger', 'clear']), ('regression: occupied before clearing', {'mode': 'auto', 'steps': [[True, False, False], [True, False, False], [False, False, False]]}, ['danger', 'danger', 'clear']), ('sampled regression 71', {'mode': 'approach', 'steps': [[False, True, False], [True, True, True], [False, True, True], [False, True, True], [True, True, True], [False, True, False]]}, ['danger', 'danger', 'clear', 'clear', 'danger', 'danger']), ('control 69', {'mode': 'auto', 'steps': [[False, False, False], [False, True, False], [False, True, False], [False, False, False], [False, False, True], [True, False, False], [False, False, True], [False, False, True], [False, False, False]]}, ['clear', 'clear', 'clear', 'clear', 'clear', 'danger', 'clear', 'clear', 'clear']), ('boundary: second train behind on the same route', {'mode': 'controlled', 'steps': [[False, True, True], [True, True, True], [False, True, True]]}, ['clear', 'danger', 'danger']), ('control 34', {'mode': 'approach', 'steps': [[False, True, True], [False, False, False], [False, True, True], [False, False, False], [True, False, True], [False, False, True], [True, False, False], [True, False, True]]}, ['clear', 'danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger']), ('control 37', {'mode': 'approach', 'steps': [[False, False, True], [True, False, False], [False, False, True], [False, False, True], [True, False, True], [False, False, False], [False, False, True], [False, False, True], [False, False, False]]}, ['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'danger']), ('sampled regression 40', {'mode': 'auto', 'steps': [[False, True, True], [True, True, True], [False, True, True], [False, True, False], [True, False, True], [True, False, True], [True, False, True]]}, ['clear', 'danger', 'clear', 'clear', 'danger', 'danger', 'danger'])], [('regression: occupied before clearing', {'mode': 'auto', 'steps': [[True, False, False], [True, False, False], [False, False, False]]}, ['danger', 'danger', 'clear']), ('boundary: automatic signal re-clears', {'mode': 'auto', 'steps': [[False, False, False], [True, False, True], [False, False, False]]}, ['clear', 'danger', 'clear']), ('sampled regression 79', {'mode': 'auto', 'steps': [[False, True, False], [True, True, False], [True, True, False]]}, ['clear', 'danger', 'danger']), ('boundary: route re-set after a train', {'mode': 'controlled', 'steps': [[False, True, True], [True, True, True], [False, False, True], [False, True, True]]}, ['clear', 'danger', 'danger', 'clear']), ('boundary: approach-released signal with empty approach', {'mode': 'approach', 'steps': [[False, True, False], [False, True, True]]}, ['danger', 'clear']), ('control 45', {'mode': 'approach', 'steps': [[False, False, False], [False, False, False], [False, True, False], [False, True, False], [True, True, False], [False, True, False], [False, True, False], [False, True, True]]}, ['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear']), ('control 48', {'mode': 'approach', 'steps': [[True, True, False], [False, True, True], [False, False, False], [False, False, True], [False, True, True], [True, True, False]]}, ['danger', 'clear', 'danger', 'danger', 'clear', 'danger']), ('sampled regression 51', {'mode': 'controlled', 'steps': [[False, False, True], [False, False, False], [False, True, False], [False, True, True], [True, False, True], [False, False, True], [True, True, False]]}, ['danger', 'danger', 'clear', 'clear', 'danger', 'danger', 'danger'])]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: occupied before clearing['clear', 'clear', 'clear']['danger', 'danger', 'clear']Failed
boundary: automatic signal re-clears['clear', 'clear', 'clear']['clear', 'danger', 'clear']Failed
sampled regression 12['danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger']['danger', 'clear', 'danger', 'danger', 'danger', 'danger', 'danger']Passed
boundary: second train behind on the same route['clear', 'danger', 'danger']['clear', 'danger', 'danger']Passed
boundary: route re-set after a train['clear', 'danger', 'danger', 'clear']['clear', 'danger', 'danger', 'clear']Passed
control 1['clear', 'clear', 'clear', 'clear', 'clear']['clear', 'clear', 'clear', 'clear', 'clear']Passed
control 4['danger', 'clear', 'danger', 'danger', 'danger']['danger', 'clear', 'danger', 'danger', 'danger']Passed
control 7['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear', 'clear', 'clear', 'danger']['danger', 'danger', 'danger', 'danger', 'danger', 'danger', 'clear', 'clear', 'clear', 'danger']Passed

SHA-256 / 154227ceae6eb646272fa0f01aaa82042e8d330b5e70caf28f0906e3c83e0f92

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 8 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

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Verification & scope

Stipulated toy interlocking contract for a bounded teaching model; it makes no claim of conformance to any railway signalling standard and omits real safety cases. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:47:50.665862+00:00.

Case digest / 71e2c6fb05f9a5c9aba470dd66f79f0b33cb1f52386585b948badf83df6eaed1