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### Function dependence flexibility

I'd like to declare an unknown function f. If I had one variable x, I would write

f=function('f')(x)


Instead, I would like to declare this function with a variable list (or tuple) that has unknown length at the beginning of the program. For example,

f=function('f')(x,y)


has two variables or

f=function('f')(x,y,t)


has three.

I can get a list (or tuple) containing my variables just before the function declaration:

vars=[x,y,z,t]


Then how can I declare my function like

f=function('f')(vars)


?