https://developers.arcgis.com/arcgis-rest-js/api-reference/arcgis-rest-portal/isServiceNameAvailable/
isServiceNameAvailable | ArcGIS REST JS | Esri Developer
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https://esri.github.io/arcgis-rest-js/api/portal/isServiceNameAvailable/
isServiceNameAvailable | API Reference | ArcGIS REST JS
A modular, high quality toolkit for working with the ArcGIS REST API.
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