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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 _get_file_key(self, file_path, link_path):
 """ Finds the absolute path of link_path relative to file_path. The absolute path is the key to anchors dictionary used throughout the AnchorHub process :param file_path: string file path of the file that contains the link being examined :param link_path: string. The link URL that we'd like to find the absolute path for :return: the absolute path of link_path relative to file_path """

        if os.path.isabs(link_path):
            return link_path
        else:
            file_dir = os.path.dirname(file_path)
            joined_path = os.path.join(file_dir, link_path)
            return os.path.abspath(joined_path)