python - Creating a partial function that sets a keyword argument in the original function -

not sure if possible i'm trying create partial function function positional , keyword arguments. problem is, want argument in resulting partial function set 1 of keyword arguments in original function - not 1 of positional arguments.

here original function's definition:

def cost_function(self, x, y, weights=none, lambda_param=0.0): 

i want partial function can pass scipy.minimise can find optimum weights values (weights ndarray).

so need partial function 1 argument (x say):

e.g.

cost_func(x) 

but want partial function set weights argument when calls original function:

my_network.cost_function(x, y, weights=x, lambda_param=0.0) 

(i know change original function weights argument positional not keyword argument don't want because want use function without weights argument set).

i think functools.partial meet needs

see example:

import functools def cost_function(self, x, y, weights=none, lambda_param=0.0):     print (weights)  cost_func = functools.partial(cost_function, none, 20, 30, lambda_param=2.0)   print (cost_func("yay worked!!!"))