=== HTTP code : 200 ===

Response headers
================
HTTP/1.1 200 OK
Date: Tue, 23 Jul 2019 15:27:57 GMT
X-Content-Type-Options: nosniff
Last-Modified: Wed, 20 Sep 2017 16:28:41 GMT
ETag: &quot;4e550d-559a17804c039&quot;
Content-Length: 5133581
Cache-Control: max-age=1209600
Expires: Tue, 06 Aug 2019 15:27:57 GMT
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Age: 464829
X-Cache: HIT
X-Cache-Hits: 514
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Connection: close

Request headers
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HEAD /sites/default/files/Cannabis_and_Cancer_ARblog_081115.pdf HTTP/1.1
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Host: www.drugpolicy.org
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Referer: https://ssdp.org
Connection: close


Link is valid.