I want to set "Special Price" for product from date to date programmatically by code but don't know how. I can set in admin use 

[![enter image description here][1]][1]


**then**
[![enter image description here][2]][2]

but I want use code to set programmatically. If anyone know, please advice.
  [1]: https://i.sstatic.net/gbajF.png
  [2]: https://i.sstatic.net/avvWk.png