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Code in python/ray/rllib/{evolution_strategies, dqn} adapted from
https://github.com/openai (MIT License)

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Code in python/ray/rllib/impala/vtrace.py from
https://github.com/deepmind/scalable_agent

Copyright 2018 Google LLC

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------------------
Code in python/ray/_private/prometheus_exporter.py is adapted from https://github.com/census-instrumentation/opencensus-python/blob/master/contrib/opencensus-ext-prometheus/opencensus/ext/prometheus/stats_exporter/__init__.py

# Copyright 2018, OpenCensus Authors
#
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# 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
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
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Code in python/ray/tests/modin/test_modin and 
python/ray/tests/modin/modin_test_utils adapted from:
- http://github.com/modin-project/modin/master/modin/pandas/test/test_general.py
- http://github.com/modin-project/modin/master/modin/pandas/test/utils.py

Copyright (c) 2018-2020 Modin Developers.

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you may not use this file except in compliance with the License.
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    https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
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See the License for the specific language governing permissions and
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Code in src/ray/util/logging.h is adapted from 
https://github.com/google/glog/blob/master/src/glog/logging.h.in

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Code in python/ray/_private/runtime_env/conda_utils.py is adapted from 
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Code in python/ray/_private/runtime_env/_clonevirtualenv.py is adapted from https://github.com/edwardgeorge/virtualenv-clone/blob/master/clonevirtualenv.py

Copyright (c) 2011, Edward George, based on code contained within the
virtualenv project.

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Code in python/ray/_private/async_compat.py is adapted from
https://github.com/python-trio/async_generator/blob/master/async_generator/_util.py

Copyright (c) 2022, Nathaniel J. Smith

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you may not use this file except in compliance with the License.
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   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
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See the License for the specific language governing permissions and
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