Download label by carrier and trackingNo. The response to a successful call contains the tracking number with the pdf or image type based on the media type passed in Accept header.
For eg. 'Accept'='application/pdf' will result in pdf media type ,
'Accept'='image/png' as image media type,
'Accept'='application/zpl' will provide label in the Zebra Programming Language format. When using 'application/zpl' or 'application/pdf' as the 'Accept' content types, it is recommended to include 'application/json' as a second header content to receive error messages.