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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 changeGroupImageLocal(self, image_path, thread_id=None):
 """ Changes a thread image from a local path :param image_path: Path of an image to upload and change :param thread_id: User/Group ID to change image. See :ref:`intro_threads` :raises: FBchatException if request failed """

        with get_files_from_paths([image_path]) as files:
            (image_id, mimetype), = self._upload(files)

        return self._changeGroupImage(image_id, thread_id)