Page 183 , fowlling procedure, not able to build file system because there is a problem with the #include WiFi.h .Trying to upload the LittleFS using PlatformIo , went to esp12e ,expand file system image and get the error. This is somewhat difficult to follow because what is shown in your book images are different so it make things harder to follow. I get through most of it but it takes time and patience when you see what is posted and the UI looks different.Thanks