FILE PHOTO: Greenpeace USA climbers form a blockade on

FILE PHOTO: Traffic is pictured on the Fred Hartman Bridge where Greenpeace USA climbers formed a blockade, shutting down the Houston Ship Channel, the largest fossil fuel thoroughfare in the United States, ahead of the third Democratic primary debate in nearby Houston, near Baytown, Texas, U.S. September 12, 2019. REUTERS/Jonathan Bachman

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