FILE - In this April 20, 2015 file photo, a Canadian flag with a cannabis leaf flies on Parliament Hill during a 4/20 protest in Ottawa, Ontario. Canada is following the lead of Uruguay in allowing a nationwide, legal marijuana market, although each Canadian province is working up its own rules for pot sales. The federal government and the provinces also still need to publish regulations that will govern the cannabis trade. (Adrian Wyld/The Canadian Press via AP, File)
