HTTP Body (or Entity-Body, HTTP Message Body) is an OPTIONAL is the data (or message) bytes transmitted in an HTTP transaction message immediately following the HTTP Header Fields if there is any.

The HTTP Method/HTTP Status Code line and HTTP Header Fields MUST all end with <CR><LF> (that is, a carriage return followed by a line feed). The empty line must consist of only <CR><LF> and no other whitespace.

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