Hi Shaurya,
By and large the resumes are in PDF format. Hence the code was written to include that format. To include doc or docx, u can easily use libraries like textract or docx2txt. For HTML, I guess u meant web scrapping, in that case u can use libraries like beautifulsoup. I have not come across resumes in ppt format but there is a library called python pptx which can help you extract text from ppt.