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++ BSD 3-Clause License
++
++ Copyright (c) 2014 - 2021, Syoyo Fujita and many contributors.
++ All rights reserved.
++
++ Redistribution and use in source and binary forms, with or without
++ modification, are permitted provided that the following conditions are met:
++
++ 1. Redistributions of source code must retain the above copyright notice, this
++ list of conditions and the following disclaimer.
++
++ 2. Redistributions in binary form must reproduce the above copyright notice,
++ this list of conditions and the following disclaimer in the documentation
++ and/or other materials provided with the distribution.
++
++ 3. Neither the name of the copyright holder nor the names of its
++ contributors may be used to endorse or promote products derived from
++ this software without specific prior written permission.
++
++ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
++ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
++ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
++ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
++ FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
++ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
++ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
++ CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
++ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
++ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.