Are there many ML frameworks that only work in 2.7? Scipy and numpy work in both 2.7 and 3.x, so I'd imagine (without being heavy in the field) that any new dev

Are there many ML frameworks that only work in 2.7? Scipy and numpy work in both 2.7 and 3.x, so I'd imagine (without being heavy in the field) that any new development using these scientific computing packages could be Python version agnostic as well. Is this generally not the case?