Add a pybind for Module::get_functions. (#20594)

Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/20594
ghimport-source-id: 96f8046fd3aed49d8b29312ce2f8d7e0ea5e5787

Differential Revision: D15375132

Pulled By: ZolotukhinM

fbshipit-source-id: 7ad87e29d965e459c49be1be8a08f86ed2a0b4db

torch/csrc/jit/script/init.cpp

@@ -312,6 +312,11 @@ void initJitScriptBindings(PyObject* module) {
           },
           py::return_value_policy::reference_internal)
       .def("_register_parameter", &Module::register_parameter)
+      .def(
+          "_get_functions",
+          [](Module& self) {
+            return self.class_compilation_unit().get_functions();
+          })
       .def(
           "_register_attribute",
           [](Module& self, std::string name, TypePtr type, py::object value) {