[package] PackageExporter visualization methods (#61147)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/61147
Basic tooling to enable users to see what is inside of a PackageExporter. Added methods:
- `externed/interned/mocked/denied_list()`: returns list of modules which are currently in the specified category
- `relied_on_by(module_name)`: returns list of modules which rely on `module_name`
- `dependency_graph_str()`: returns string format of graph for users. Example of output:
```
digraph G {
rankdir = LR;
node [shape=box];
"<res.foo.pkl>" -> "foo";
"foo" -> "torch.package";
"foo" -> "time";
"foo" -> "sentencepiece";
"foo" -> "package_top";
}
```
Test Plan: Imported from OSS
Reviewed By: suo
Differential Revision: D29559683
Pulled By: Lilyjjo
fbshipit-source-id: 5dff4d04af911a9c9fdd0d100420f1382eaef46e
