lambdify sympy with Variable-Length Arguments

Question

I have a list of expr with a different number of variables as follows:

G = [[-x_1 + y_1], [-x_2 + y_1 + y_2], [y_1 + y_2] , [-y_3] , ....]

I want to evaluate these expressions using sympy and lambdify. For this purpose, I have written the following instructions:

def f(item):
    return lamndify(list(tem.free_symbols), item)



for  item in G:
    f_ = f(item)
    ...

Now, what should I do to call f_ because there are different variables in each term?