Empty data while parsing markdown

[vsumit89]

// some code above here

markdownData := `
# Programming and C Language Notes

### What is Programming?
- Computer programming is a means for us to communicate with computers.
- Similar to using languages like Hindi or English to communicate with each other; programming is our way of delivering instructions to the computer.

### What is C?
- C is a programming language.
- It is one of the oldest and finest programming languages.
- Developed by Dennis Ritchie at AT&T's Bell Labs, USA in 1972.

### Uses of C
- C language is utilized to program a wide variety of systems.
- Some common uses include:
        - Major parts of Windows, Linux, and other operating systems are written in C.
        - C is used for writing device drivers for devices such as tablets and printers.
        - It is employed in programming embedded systems where programs need to run fast in limited memory (e.g., microwaves, cameras).
        - C plays a role in developing games as it's important for a computer to react quickly to user input where latency is critical.
`

parser := blackfriday.New()

ast := parser.Parse([]byte(markdownData))

fmt.Println(ast)

// some code below

the print shows an empty result the blocks contain no data. Is there anything I am doing wrong?