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### Use assume() on find_fit

Hi everyone,

does anyone know how I can use assumptions with find_fit? A minimal example would be

var('a,b,x')
assume(a>0,b>0)
find_fit([(2,2),(3,2.9),(4,4.1)],(a+1)/b*x,variables=[x],initial_guess=(-2,-2))


and the output is

[a == -105.66654155674746, b == -104.30685450333799]


Any help or hint on where to find a solution is appriciated. Thanks in advance.