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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 parse_filepath(self, filepath=None):
 """ Parse given filepath to split possible path directory from filename. * If path directory is empty, will use ``basedir`` attribute as base filepath; * If path directory is absolute, ignore ``basedir`` attribute; * If path directory is relative, join it to ``basedir`` attribute; Keyword Arguments: filepath (str):
 Filepath to use to search for settings file. Will use value from ``_default_filename`` class attribute if empty. If filepath contain a directory path, it will be splitted from filename and used as base directory (and update object ``basedir`` attribute). Returns: tuple: Separated path directory and filename. """

        filepath = filepath or self._default_filename

        path, filename = os.path.split(filepath)

        if not path:
            path = self.basedir
        elif not os.path.isabs(path):
            path = os.path.join(self.basedir, path)

        return os.path.normpath(path), filename