defined as an OPTIONAL means for indicating the tracking status that applied to the corresponding request and as a REQUIRED means for indicating that a state-changing request has resulted in an interactive change to the tracking status.
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Description
defined as an OPTIONAL means for indicating the tracking status that applied to the corresponding request and as a REQUIRED means for indicating that a state-changing request has resulted in an interactive change to the tracking status.
Syntax
Frequently asked questions
defined as an OPTIONAL means for indicating the tracking status that applied to the corresponding request and as a REQUIRED means for indicating that a state-changing request has resulted in an interactive change to the tracking status.
It is classified as a response header and can appear in requests or responses depending on context.
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