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A medical marijuana patient pays for product through a teller window at Medex, a dispensary on Century Boulevard in South Los Angeles.

Medical marijuana patients Daquan Giles, 23, left, and Nana Whitfield, 21, check out products at Medex on Century Boulevard.

Medical marijuana patient Nana Whitfield, 21, looks at samples at Medex.

Marijuana in jars at Medex, a dispensary on Century Boulevard in South Los Angeles.