westonpace commented on code in PR #12590: URL: https://github.com/apache/arrow/pull/12590#discussion_r856379848
########## cpp/src/arrow/python/udf.cc: ########## @@ -0,0 +1,132 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you under the Apache License, Version 2.0 (the +// "License"); you may not use this file except in compliance +// with the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, +// software distributed under the License is distributed on an +// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +// KIND, either express or implied. See the License for the +// specific language governing permissions and limitations +// under the License. + +#include "arrow/python/udf.h" + +#include <cstddef> +#include <memory> +#include <sstream> + +#include "arrow/compute/function.h" +#include "arrow/python/common.h" + +namespace arrow { + +namespace py { + +Status CheckOutputType(const DataType& expected, const DataType& actual) { + if (!expected.Equals(actual)) { + return Status::TypeError("Expected output type, ", expected.name(), + ", but function returned type ", actual.name()); + } + return Status::OK(); +} + +struct PythonUdf { + ScalarUdfWrapperCallback cb; + std::shared_ptr<OwnedRefNoGIL> function; + compute::OutputType output_type; + + // function needs to be destroyed at process exit + // and Python may no longer be initialized. + ~PythonUdf() { + if (_Py_IsFinalizing()) { + function->detach(); + } + } + + Status operator()(compute::KernelContext* ctx, const compute::ExecBatch& batch, + Datum* out) { + return SafeCallIntoPython([=]() -> Status { return Execute(ctx, batch, out); }); + } + + Status Execute(compute::KernelContext* ctx, const compute::ExecBatch& batch, + Datum* out) { + const auto num_args = batch.values.size(); + ScalarUdfContext udf_context{ctx->memory_pool(), static_cast<int64_t>(num_args)}; Review Comment: ```suggestion ScalarUdfContext udf_context{ctx->memory_pool(), static_cast<int64_t>(batch.length)}; ``` ########## python/pyarrow/tests/test_udf.py: ########## @@ -0,0 +1,545 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + + +import pytest + +import pyarrow as pa +from pyarrow import compute as pc + + +# Marks all of the tests in this module +# Ignore these with pytest ... -m 'not udf' +# pytestmark = pytest.mark.udf + +unary_doc = {"summary": "add function", + "description": "test add function"} + + [email protected](scope="session") +def udf_context(): + return pc._get_scalar_udf_context(pa.default_memory_pool(), 0) + + [email protected](scope="session") +def unary_func_fixture(): + def unary_function(udf_context, scalar1): + return pc.call_function("add", [scalar1, 1]) + return unary_function + + +binary_doc = {"summary": "y=mx", + "description": "find y from y = mx"} + + [email protected](scope="session") +def binary_func_fixture(): + def binary_function(ctx, m, x): + return pc.call_function("multiply", [m, x]) + return binary_function + + +ternary_doc = {"summary": "y=mx+c", + "description": "find y from y = mx + c"} + + [email protected](scope="session") +def ternary_func_fixture(): + def ternary_function(ctx, m, x, c): + mx = pc.call_function("multiply", [m, x]) + return pc.call_function("add", [mx, c]) + return ternary_function + + +varargs_doc = {"summary": "z=ax+by+c", + "description": "find z from z = ax + by + c" + } + + [email protected](scope="session") +def varargs_func_fixture(): + def varargs_function(ctx, *values): + base_val = values[:2] + res = pc.call_function("add", base_val) + for other_val in values[2:]: + res = pc.call_function("add", [res, other_val]) + return res + return varargs_function + + [email protected](scope="session") +def random_with_udf_ctx_func_fixture(): + def random_with_udf_ctx(context, one, two): + old_pool = pa.default_memory_pool() + proxy_pool = pa.proxy_memory_pool(context.memory_pool) + pa.set_memory_pool(proxy_pool) + try: + ans = pc.add(one, two, memory_pool=proxy_pool) + allocated_before = proxy_pool.bytes_allocated() + # allocating 64 bytes + res = pa.array([ans.as_py()], memory_pool=proxy_pool) + allocated_after = proxy_pool.bytes_allocated() + finally: + pa.set_memory_pool(old_pool) + assert allocated_before == 0 + assert allocated_after == 64 Review Comment: ```suggestion ans = pc.add(one, two, memory_pool=proxy_pool) res = pa.array([ans.as_py()], memory_pool=proxy_pool) ``` There is no reason to change the default memory pool (and a real user shouldn't as that could be dangerous). The important fact is that you are passing it to the call to `pc.add` and `pa.array`. Also, checking bytes allocated here is just testing that `pc.add` is doing the right thing and that isn't very interesting (well, it might be interesting, but only for `test_compute.py`). The C++ layer could be giving you the completely wrong memory pool and this check would still pass. ########## python/pyarrow/tests/test_udf.py: ########## @@ -0,0 +1,545 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + + +import pytest + +import pyarrow as pa +from pyarrow import compute as pc + + +# Marks all of the tests in this module +# Ignore these with pytest ... -m 'not udf' +# pytestmark = pytest.mark.udf + +unary_doc = {"summary": "add function", + "description": "test add function"} + + [email protected](scope="session") +def udf_context(): + return pc._get_scalar_udf_context(pa.default_memory_pool(), 0) + + [email protected](scope="session") +def unary_func_fixture(): + def unary_function(udf_context, scalar1): + return pc.call_function("add", [scalar1, 1]) + return unary_function + + +binary_doc = {"summary": "y=mx", + "description": "find y from y = mx"} + + [email protected](scope="session") +def binary_func_fixture(): + def binary_function(ctx, m, x): + return pc.call_function("multiply", [m, x]) + return binary_function + + +ternary_doc = {"summary": "y=mx+c", + "description": "find y from y = mx + c"} + + [email protected](scope="session") +def ternary_func_fixture(): + def ternary_function(ctx, m, x, c): + mx = pc.call_function("multiply", [m, x]) + return pc.call_function("add", [mx, c]) + return ternary_function + + +varargs_doc = {"summary": "z=ax+by+c", + "description": "find z from z = ax + by + c" + } + + [email protected](scope="session") +def varargs_func_fixture(): + def varargs_function(ctx, *values): + base_val = values[:2] + res = pc.call_function("add", base_val) + for other_val in values[2:]: + res = pc.call_function("add", [res, other_val]) + return res + return varargs_function + + [email protected](scope="session") +def random_with_udf_ctx_func_fixture(): + def random_with_udf_ctx(context, one, two): + old_pool = pa.default_memory_pool() + proxy_pool = pa.proxy_memory_pool(context.memory_pool) + pa.set_memory_pool(proxy_pool) + try: + ans = pc.add(one, two, memory_pool=proxy_pool) + allocated_before = proxy_pool.bytes_allocated() + # allocating 64 bytes + res = pa.array([ans.as_py()], memory_pool=proxy_pool) + allocated_after = proxy_pool.bytes_allocated() + finally: + pa.set_memory_pool(old_pool) + assert allocated_before == 0 + assert allocated_after == 64 + assert context.batch_length == 2 Review Comment: We don't need to assert this here and doing so is a little messy because now this function has to know about the test that calls it. ########## python/pyarrow/tests/test_udf.py: ########## @@ -0,0 +1,545 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + + +import pytest + +import pyarrow as pa +from pyarrow import compute as pc + + +# Marks all of the tests in this module +# Ignore these with pytest ... -m 'not udf' +# pytestmark = pytest.mark.udf + +unary_doc = {"summary": "add function", + "description": "test add function"} + + [email protected](scope="session") +def udf_context(): + return pc._get_scalar_udf_context(pa.default_memory_pool(), 0) + + [email protected](scope="session") +def unary_func_fixture(): + def unary_function(udf_context, scalar1): + return pc.call_function("add", [scalar1, 1]) + return unary_function + + +binary_doc = {"summary": "y=mx", + "description": "find y from y = mx"} + + [email protected](scope="session") +def binary_func_fixture(): + def binary_function(ctx, m, x): + return pc.call_function("multiply", [m, x]) + return binary_function + + +ternary_doc = {"summary": "y=mx+c", + "description": "find y from y = mx + c"} + + [email protected](scope="session") +def ternary_func_fixture(): + def ternary_function(ctx, m, x, c): + mx = pc.call_function("multiply", [m, x]) + return pc.call_function("add", [mx, c]) + return ternary_function + + +varargs_doc = {"summary": "z=ax+by+c", + "description": "find z from z = ax + by + c" + } + + [email protected](scope="session") +def varargs_func_fixture(): + def varargs_function(ctx, *values): + base_val = values[:2] + res = pc.call_function("add", base_val) + for other_val in values[2:]: + res = pc.call_function("add", [res, other_val]) + return res + return varargs_function + + [email protected](scope="session") +def random_with_udf_ctx_func_fixture(): + def random_with_udf_ctx(context, one, two): + old_pool = pa.default_memory_pool() + proxy_pool = pa.proxy_memory_pool(context.memory_pool) + pa.set_memory_pool(proxy_pool) + try: + ans = pc.add(one, two, memory_pool=proxy_pool) + allocated_before = proxy_pool.bytes_allocated() + # allocating 64 bytes + res = pa.array([ans.as_py()], memory_pool=proxy_pool) + allocated_after = proxy_pool.bytes_allocated() + finally: + pa.set_memory_pool(old_pool) + assert allocated_before == 0 + assert allocated_after == 64 + assert context.batch_length == 2 + return res Review Comment: This return value isn't correct. You are returning an array of size 1 no matter what the `batch_length` was. This violates the rules for a "scalar function" which must emit an item for each row. ########## python/pyarrow/tests/test_udf.py: ########## @@ -0,0 +1,545 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + + +import pytest + +import pyarrow as pa +from pyarrow import compute as pc + + +# Marks all of the tests in this module +# Ignore these with pytest ... -m 'not udf' +# pytestmark = pytest.mark.udf + +unary_doc = {"summary": "add function", + "description": "test add function"} Review Comment: If we get rid of scalar tests then this is only used by one function so we can move it into the fixture body. ########## python/pyarrow/tests/test_udf.py: ########## @@ -0,0 +1,545 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + + +import pytest + +import pyarrow as pa +from pyarrow import compute as pc + + +# Marks all of the tests in this module +# Ignore these with pytest ... -m 'not udf' +# pytestmark = pytest.mark.udf + +unary_doc = {"summary": "add function", + "description": "test add function"} + + [email protected](scope="session") +def udf_context(): Review Comment: Nit: mock_udf_context? ########## python/pyarrow/tests/test_udf.py: ########## @@ -0,0 +1,545 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + + +import pytest + +import pyarrow as pa +from pyarrow import compute as pc + + +# Marks all of the tests in this module +# Ignore these with pytest ... -m 'not udf' +# pytestmark = pytest.mark.udf + +unary_doc = {"summary": "add function", + "description": "test add function"} + + [email protected](scope="session") +def udf_context(): + return pc._get_scalar_udf_context(pa.default_memory_pool(), 0) + + [email protected](scope="session") +def unary_func_fixture(): + def unary_function(udf_context, scalar1): + return pc.call_function("add", [scalar1, 1]) + return unary_function + + +binary_doc = {"summary": "y=mx", + "description": "find y from y = mx"} + + [email protected](scope="session") +def binary_func_fixture(): + def binary_function(ctx, m, x): + return pc.call_function("multiply", [m, x]) + return binary_function + + +ternary_doc = {"summary": "y=mx+c", + "description": "find y from y = mx + c"} + + [email protected](scope="session") +def ternary_func_fixture(): + def ternary_function(ctx, m, x, c): + mx = pc.call_function("multiply", [m, x]) + return pc.call_function("add", [mx, c]) + return ternary_function + + +varargs_doc = {"summary": "z=ax+by+c", + "description": "find z from z = ax + by + c" + } + + [email protected](scope="session") +def varargs_func_fixture(): + def varargs_function(ctx, *values): + base_val = values[:2] + res = pc.call_function("add", base_val) + for other_val in values[2:]: + res = pc.call_function("add", [res, other_val]) + return res + return varargs_function + + [email protected](scope="session") +def random_with_udf_ctx_func_fixture(): + def random_with_udf_ctx(context, one, two): + old_pool = pa.default_memory_pool() + proxy_pool = pa.proxy_memory_pool(context.memory_pool) Review Comment: ```suggestion ``` Proxy the memory pool in the calling portion (in the test) and we can assert it there. ########## python/pyarrow/tests/test_udf.py: ########## @@ -0,0 +1,545 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + + +import pytest + +import pyarrow as pa +from pyarrow import compute as pc + + +# Marks all of the tests in this module +# Ignore these with pytest ... -m 'not udf' +# pytestmark = pytest.mark.udf + +unary_doc = {"summary": "add function", + "description": "test add function"} + + [email protected](scope="session") +def udf_context(): + return pc._get_scalar_udf_context(pa.default_memory_pool(), 0) + + [email protected](scope="session") +def unary_func_fixture(): + def unary_function(udf_context, scalar1): + return pc.call_function("add", [scalar1, 1]) + return unary_function + + +binary_doc = {"summary": "y=mx", + "description": "find y from y = mx"} + + [email protected](scope="session") +def binary_func_fixture(): + def binary_function(ctx, m, x): + return pc.call_function("multiply", [m, x]) + return binary_function + + +ternary_doc = {"summary": "y=mx+c", + "description": "find y from y = mx + c"} + + [email protected](scope="session") +def ternary_func_fixture(): + def ternary_function(ctx, m, x, c): + mx = pc.call_function("multiply", [m, x]) + return pc.call_function("add", [mx, c]) + return ternary_function + + +varargs_doc = {"summary": "z=ax+by+c", + "description": "find z from z = ax + by + c" + } + + [email protected](scope="session") +def varargs_func_fixture(): + def varargs_function(ctx, *values): + base_val = values[:2] + res = pc.call_function("add", base_val) + for other_val in values[2:]: + res = pc.call_function("add", [res, other_val]) + return res + return varargs_function + + [email protected](scope="session") +def random_with_udf_ctx_func_fixture(): + def random_with_udf_ctx(context, one, two): + old_pool = pa.default_memory_pool() + proxy_pool = pa.proxy_memory_pool(context.memory_pool) + pa.set_memory_pool(proxy_pool) + try: + ans = pc.add(one, two, memory_pool=proxy_pool) + allocated_before = proxy_pool.bytes_allocated() + # allocating 64 bytes + res = pa.array([ans.as_py()], memory_pool=proxy_pool) + allocated_after = proxy_pool.bytes_allocated() + finally: + pa.set_memory_pool(old_pool) + assert allocated_before == 0 + assert allocated_after == 64 + assert context.batch_length == 2 + return res + return random_with_udf_ctx + + [email protected](scope="session") +def const_return_func_fixture(): + def const_return(ctx, array): + return 42 + return const_return + + [email protected](scope="session") +def output_check_func_fixture(): + def output_check(ctx, array): + ar = pc.call_function("add", [array, 1]) + ar = ar.cast(pa.int32()) + return ar + return output_check + + [email protected](scope="session") +def nullary_check_func_fixture(): + def nullary_check(ctx): + import random Review Comment: We can just import this at the top of the file. I see no need to nest this import. ########## python/pyarrow/tests/test_udf.py: ########## @@ -0,0 +1,545 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + + +import pytest + +import pyarrow as pa +from pyarrow import compute as pc + + +# Marks all of the tests in this module +# Ignore these with pytest ... -m 'not udf' +# pytestmark = pytest.mark.udf Review Comment: We probably don't need a mark since we always compile with the support. We may want to depend on the dataset mark if we are going to run in datasets. ########## python/pyarrow/tests/test_udf.py: ########## @@ -0,0 +1,545 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + + +import pytest + +import pyarrow as pa +from pyarrow import compute as pc + + +# Marks all of the tests in this module +# Ignore these with pytest ... -m 'not udf' +# pytestmark = pytest.mark.udf + +unary_doc = {"summary": "add function", + "description": "test add function"} + + [email protected](scope="session") +def udf_context(): + return pc._get_scalar_udf_context(pa.default_memory_pool(), 0) + + [email protected](scope="session") +def unary_func_fixture(): + def unary_function(udf_context, scalar1): + return pc.call_function("add", [scalar1, 1]) + return unary_function + + +binary_doc = {"summary": "y=mx", + "description": "find y from y = mx"} + + [email protected](scope="session") +def binary_func_fixture(): + def binary_function(ctx, m, x): + return pc.call_function("multiply", [m, x]) + return binary_function + + +ternary_doc = {"summary": "y=mx+c", + "description": "find y from y = mx + c"} + + [email protected](scope="session") +def ternary_func_fixture(): + def ternary_function(ctx, m, x, c): + mx = pc.call_function("multiply", [m, x]) + return pc.call_function("add", [mx, c]) + return ternary_function + + +varargs_doc = {"summary": "z=ax+by+c", + "description": "find z from z = ax + by + c" + } + + [email protected](scope="session") +def varargs_func_fixture(): + def varargs_function(ctx, *values): + base_val = values[:2] + res = pc.call_function("add", base_val) + for other_val in values[2:]: + res = pc.call_function("add", [res, other_val]) + return res + return varargs_function + + [email protected](scope="session") +def random_with_udf_ctx_func_fixture(): + def random_with_udf_ctx(context, one, two): + old_pool = pa.default_memory_pool() + proxy_pool = pa.proxy_memory_pool(context.memory_pool) + pa.set_memory_pool(proxy_pool) + try: + ans = pc.add(one, two, memory_pool=proxy_pool) + allocated_before = proxy_pool.bytes_allocated() + # allocating 64 bytes + res = pa.array([ans.as_py()], memory_pool=proxy_pool) + allocated_after = proxy_pool.bytes_allocated() + finally: + pa.set_memory_pool(old_pool) + assert allocated_before == 0 + assert allocated_after == 64 + assert context.batch_length == 2 + return res + return random_with_udf_ctx + + [email protected](scope="session") +def const_return_func_fixture(): + def const_return(ctx, array): + return 42 + return const_return + + [email protected](scope="session") +def output_check_func_fixture(): + def output_check(ctx, array): + ar = pc.call_function("add", [array, 1]) + ar = ar.cast(pa.int32()) + return ar + return output_check + + [email protected](scope="session") +def nullary_check_func_fixture(): + def nullary_check(ctx): + import random + val = random.randint(0, 10) + return pa.scalar(val) + return nullary_check + + [email protected](scope="session") +def add_const_func_fixture(): Review Comment: There is no need for this fixture because the only tests that use it do not successfully register the function. -- This is an automated message from the Apache Git Service. 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