def _is_analytic(f, x):
 from sympy import Heaviside, Abs
 return (not any(((x in expr.free_symbols) for expr in f.atoms(Heaviside, Abs))))

def _is_analytic ( f , x ) : from sympy import Heaviside , Abs return ( not any ( ( ( x in expr . free_symbols ) for expr in f . atoms ( Heaviside , Abs ) ) ) )
check if f(x) .