I am not developer, so my question is probably ridiculous. I have an error (see the message below) for the two lines starting by `sum1` `sum2`. 

Code:

```py
#Get single constituent sinusoid on z
sx(i, k, N) =>
    sum1 = ReX_(k)*cos(2*pi*k*i/N)
    sum2 = ImX_(k)*sin(2*pi*k*i/N)
    return = sum1+sum2

```

Error:

> 
> Cannot call 'anonym\_function\_2' with arguments (fun\_arg\_\_, fun\_arg\_\_, fun\_arg\_\_, series[float]);
> 
> 
> 

Can you tell me if there is a syntax error?

Thank you.