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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_fs(self, create_dir=True):
 """Return tuple with filesystem and filename."""

        filedir = dirname(self.fileurl)
        filename = basename(self.fileurl)

        return (
            opener.opendir(filedir, writeable=True, create_dir=create_dir),
            filename
        )