'Filters `sk_params` and return those in `fn`\'s arguments.
# Arguments
fn : arbitrary function
override: dictionary, values to override sk_params
# Returns
res : dictionary dictionary containing variables
in both sk_params and fn\'s arguments.'

def filter_sk_params(self, fn, override=None):

    override = (override or {})
    res = {}
    for (name, value) in self.sk_params.items():
        if has_arg(fn, name):
            res.update({name: value})
    res.update(override)
    return res
