Not load torch lib if not necessary

When running some scripts or unit-tests torch lib is loaded. That makes the running slow.

Torch shouldn't get imported when it's not necessary

For example, there can be a case when module `lib` has functions `func1` and `func2`. However, only `func1` uses torch library. Thus, if some module needs to use `func2`, torch will still be loaded because, it's normally imported globally in a module.

The issue does not name a file or specific test. Start by tracing which module-level import loads torch when running the affected scripts or unit-tests, then compare paths that use only functions such as func2. Done means torch is not loaded for paths that do not need it, while the relevant unit-tests still pass.

Written by the indexing model from the issue text.