#### Description of the problem <!--Please provide a clear and details information of the bug/data structure to be added.--> The `doc` folder should contain the mechanism for building the doc strings. #### Example of the problem <!--Provide a reproducible example code which is causing the bug to appear. Leave this section if the problem is not a bug.--> #### References/Other comments Refer, https://github.com/sympy/sympy/tree/master/doc