Closest Facility Field Mappings arcpy.nax

[Kristen]

The documentation lists ID field, but I am not able to access it with field mappings. I get a Key Error when trying ID or IncidentID. Name works fine.

# Construct a field mapping object
field_mappings = closest_facility.fieldMappings(arcpy.nax.ClosestFacilityInputDataType.Incidents)

# Map the field from your input data to the incidents
# class's Incident ID
# field_mappings["IncidentID"].mappedFieldName = "ADDRESS_KEY" # KeyError: 'IncidentID'
field_mappings["ID"].mappedFieldName = "ADDRESS_KEY" # KeyError: 'ID'
# field_mappings["Name"].mappedFieldName = 'ADDRESS_KEY' # works

---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
<ipython-input-144-2a71c2ff6a31> in <module>
      5 # class's Incident ID
      6 # field_mappings["IncidentID"].mappedFieldName = "ADDRESS_KEY" # KeyError: 'IncidentID'
----> 7 field_mappings["ID"].mappedFieldName = "ADDRESS_KEY" # KeyError: 'ID'
      8 # field_mappings["Name"].mappedFieldName = 'ADDRESS_KEY' # works

KeyError: 'ID'

for f in field_mappings:
    print(f)

Name
TargetFacilityCount
CurbApproach
AdditionalTime
AdditionalDistance
AdditionalCost
Cutoff
Bearing
BearingTol
NavLatency

How do you populate the ID?

ArcGIS Pro 2.9.2

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