How do you unpack a tuple of variable number of parameters (*args) inside a function?

What I have tried:

def df(t,x,*system_constants):
a,b,c,d,e,f,g,h,i,j,k,l,m = system_constants #unpack system constants
    #algebra with these constants to calculate something
    return something

This returns an error when called, saying:
"ValueError: not enough values to unpack (expected 13, got 0).

Also (regardless of this error), it might be better to use a short form unpacking with a for loop. What would this for loop look like?

def df(t,x,*system_constants):

    for arg in system_constants:
        arg = system_constants
    #algebra with these constants to calculate something
    return something

The only objective here is to pass a tuple to a function without getting the above error, such that I can use the arguments without calling by index (i.e. without converting to a list)

The function is being called as an argument to the scipy.solve_ivp integrator:

sol = solve_ivp(df, [t0,tf], x0, dense_output = True)

The system_constants are stored in the same script just simply as:

system_constants = a,b,c,d,e,f,g,h,i,j,k,l,m

>Solution :

According to the documentation,

The calling signature is fun(t, y).

The function is only called with 2 arguments, you are expecting 15. That won’t work.