[OpenVINO BACKEND] - feat: implement numpy.nonzero for openvino backend (#21163)

* feat: implement numpy.nonzero for openvino backend

Signed-off-by: 11happy <[email protected]>

* format code

Signed-off-by: 11happy <[email protected]>

---------

Signed-off-by: 11happy <[email protected]>

Author: 11happy

keras/src/backend/openvino/excluded_concrete_tests.txt

@@ -39,7 +39,6 @@ NumpyDtypeTest::test_min
 NumpyDtypeTest::test_moveaxis
 NumpyDtypeTest::test_multiply
 NumpyDtypeTest::test_nan
-NumpyDtypeTest::test_nonzero
 NumpyDtypeTest::test_outer_
 NumpyDtypeTest::test_power
 NumpyDtypeTest::test_prod
@@ -98,7 +97,6 @@ NumpyOneInputOpsCorrectnessTest::test_meshgrid
 NumpyOneInputOpsCorrectnessTest::test_min
 NumpyOneInputOpsCorrectnessTest::test_moveaxis
 NumpyOneInputOpsCorrectnessTest::test_nan_to_num
-NumpyOneInputOpsCorrectnessTest::test_nonzero
 NumpyOneInputOpsCorrectnessTest::test_pad_float16_constant_2
 NumpyOneInputOpsCorrectnessTest::test_pad_float32_constant_2
 NumpyOneInputOpsCorrectnessTest::test_pad_float64_constant_2

keras/src/backend/openvino/numpy.py

@@ -1043,9 +1043,9 @@ def ndim(x):
 
 
 def nonzero(x):
-    raise NotImplementedError(
-        "`nonzero` is not supported with openvino backend"
-    )
+    x = get_ov_output(x)
+    res = ov_opset.non_zero(data=x, output_type="i32").output(0)
+    return OpenVINOKerasTensor(res)
 
 
 def not_equal(x1, x2):