You can use the TeamfightTactics variable to create commands that display rank information for a summoner name.
summoner_name is the summoner name being looked up
region is the region the summoner plays on
$(teamfighttactics testing na)
would result in
testing's current rank: Challenger I
Adding a command to show chatters your rank
!commands add !rank $(teamfighttactics
Adding a command to allow users in chat to lookup their own account
!commands add !rank $(teamfighttactics $(query))
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