"Library not found for -lbullet"

Hi, 

My game uploaded fine to my phone from Xcode but it's not cleaning and building it to upload to the App Store. When building it, an error message reads, "Library not found for -lbullet". I posted on StackOverflow​ and asked some friends. Nobody was able to tell me what library this is. Any help would be greatly appreciated. Thank you so much. - Adam
"Library not found for -lbullet"
 
 
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