Add test for copy_ op #918

Author: vidursatija

coremltools/converters/mil/frontend/torch/test/test_torch_ops.py

@@ -4759,3 +4759,14 @@ def forward(self, x):
             backend=backend,
             converter_input_type=converter_input_type,
         )
+
+
+class TestCopy:
+    @pytest.mark.parametrize(
+        "backend, rank", itertools.product(backends, list(range(1, 6))),
+    )
+    def test_copy(self, backend, rank):
+        input_shape = tuple(np.random.randint(low=2, high=6, size=rank))
+
+        model = ModuleWrapper(function=lambda x: x.copy_())
+        run_compare_torch(input_shape, model, backend=backend)