Mayor Eric Adams made his first public visit to a Big Apple pot shop and walked away with a free “weed bag” — but not the kind with marijuana in it. Adams was gifted a customized leather tote bag branding him “The Cannabis Mayor Eric Adams” as he cut the ribbon at the grand opening of Matawana Dispensary in Park Slope — the city’s 36th legal marijuana store and the first owned by a black woman. “What’s in it?” Adams said as he shook the empty bag, which was covered with images of marijuana buds.