Displaying all symbolic expression with ExpressionNice

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Hi,

Is there a way of turning ExpressionNice the default way of displaying all my symbolic expression? Instead of importing and calling it like in

from sage.manifolds.utilities import ExpressionNice
var('y')
f = function('f')(x, y)
fun = f.diff(x,x,y,y,x)*x
ExpressionNice(fun)