Create a requirements.txt with version specified.

[puthusseri]

As the file requirements.txt only contains the name of the libraries used, it will be hard to get the exact working environment in the future. So if possible try to export the environment so that it will contain the required modules with its version that can run the code smoothly.

[sukhjit]

This PR should solve the issue: https://github.com/jofpin/trape/pull/297