Sample code:
```mermaid
gantt
dateFormat YYYY-MM-DD
title GANNT
section section1
w1 :done, w1, 2022-11-01, 2022-11-06
w1 :done, w2, after w1, 2d
w3 :done, w3, after w2, 2022-11-23
m1 :milestone, m1, 2022-11-23 , 0d
w4 :active, w4, after w2, 2022-11-27
w5 :w5, after w4, 3d
w6 :w6, after w5, 2d
section section2
c1 :c1, 2023-01-16, 2023-01-28
section section3
dp1 :active, dp1, 2022-11-01, 2022-11-25
dp2 :dp2, after w6 dp1, 2022-12-23
dp3 :dp3, 2023-01-16, 2023-03-31
m2 :milestone, m2, 2023-03-31, 0d
dp4 :active, dp4, 2022-11-01, 2023-03-31
section section4
md1 :md1, 2023-03-01, 2023-03-31