im the author of pygsheets (a library for acessing google sheets from python) https://github.com/nithinmurali/pygsheets. As mentioned in other comments i think you will only get contributions if your project is useful. the project will only grow if it has some users. once you have some users you will start getting issues created. you would have to fix some issues at first. Now if your project has a good enough documentation. you will start getting some pull requests. it will go uphill from there.