Property subscribe does not exist on type subscription

Ionic Framework ionic-v3
1

Hi, everyone i am getting this error.

image

here is my code:

return this.http.post(this.LOGIN_URL, body, {headers: this.contentHeader})
.map((res:Response) => res.json())
.subscribe(
data => { this.mydata = data}
);

please guide me where i am doing wrong.

thanks