Error in defining custom function for electrolyte diffusivity

[kumaryash7]

import pybamm as pb
import numpy as np
import pandas as pd

pb.set_logging_level("NOTICE")
model = pb.lithium_ion.DFN()
param = pb.ParameterValues("Chen2020")

// my custom function which has liquid phase concentration and temp as parameters
def electrolyte_diffusivity(c,T):
return (10**(-4.43-(54/(T-(229+5c)))-0.22c))*(10**-4)

// calling the custom function
// my concentration parameter will take the input from model.variables() as the liq phase concentration is constantly varying during the experiment.
param['Electrolyte diffusivity [m2.s-1]']=electrolyte_diffusivity(model.variables['Electrolyte concentration'],param['Ambient temperature [K]'])

// running this experiment gives the following error
experiment = pb.Experiment(
[
(
"Charge at 1 C until 4.2 V",
"Hold at 4.2 V until C/10",

        "Discharge at 1 C until 2.75 V",
        
    )
]
*1

)
sim = pb.Simulation(model, experiment=experiment, parameter_values=param)
sim.solve(solver=pb.CasadiSolver(mode="safe"))
sim.plot(
[
'Terminal voltage [V]',
'Discharge capacity [A.h]',

]

)

//error --> TypeError: Parameter provided for 'Electrolyte diffusivity [m2.s-1]' is of the wrong type (should either be scalar-like or callable)

[valentinsulzer]

Just do param['Electrolyte diffusivity [m2.s-1]']=electrolyte_diffusivity