Golang语法错误：写入文件时发生意外的EOF

syntax error: unexpected EOF

b, err := json.Marshal(gfjson) 
    if err != nil { 
     panic(err) 

    filename := ".gfjson" 

    f, err := os.Create(filename) 
    if err != nil { 
     panic(err) 
    } 
    // close file on exit and check for returned error 
    defer func() { 
     if err := f.Close(); err != nil { 
      panic(err) 
     } 
    }() 


    if _, err := f.Write(b); err != nil { 
     panic(err) 
    } 

    fmt.Fprintf(os.Stdout, "GFJSON file successfully created.\n") 
}