PyCWT is released under a BSD-style open source licence:

Copyright (c) 2017 Sebastian Krieger, Nabil Freij, Alexey Brazhe, 
Christopher Torrence, Gilbert P. Compo and 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.
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   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.

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