how many teams have used the stadium which hosted the gymnastics at the 2016 summer olympics – men's trampoline ?
SELECT DISTINCT COUNT attr_open var_uri attr_close where brack_open dbr_Gymnastics_at_the_2016_Summer_Olympics_–_Men's_trampoline dbp_venue var_x sep_dot var_x dbo_tenant var_uri sep_dot var_x a dbo_Stadium brack_close