How to change the project facet Dynamic web module in eclipse

Here is another post on changing the dynamic web module version inside eclipse.
This is very easy to change the version of the facet in eclipse.

The steps to change the version is as follows:

1) Right click on project and select properties

2) Click on Project Facets in properties tab. Inside project facet window there is an option  for check-box selection for Dynamic Web Module version.
  
   a) First Un-check the check-box

   b) Now change the version as per the requirement. Click on apply and Ok.

Now the project facet dynamic web module is changed to required version.