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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def change_extension(self, filepath, new_extension):
 """ Change final filename extension. Args: filepath (str):
 A file path (relative or absolute). new_extension (str):
 New extension name (without leading dot) to apply. Returns: str: Filepath with new extension. """

        filename, ext = os.path.splitext(filepath)
        return '.'.join([filename, new_extension])