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Git commits in Moodle 3.5.1 by David Balch
commit f93f81a9f6dce36a3ddc787dd49ec97516bda0e4 Author: David Balch <david.balch@conted.ox.ac.uk> Date: Mon, 28 May 2018 12:42:16 +0800 Tag: v3.5.1 MDL-57742 core_lib: Make tool_consumer_instance_guid optional