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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 _delegate(self, path):
 # type: (Text) -> Tuple[FS, Text] """Get the delegate FS for a given path. Arguments: path (str):
 A path. Returns: (FS, str):
 a tuple of ``(<fs>, <path>)`` for a mounted filesystem, or ``(None, None)`` if no filesystem is mounted on the given ``path``. """

        _path = forcedir(abspath(normpath(path)))
        is_mounted = _path.startswith

        for mount_path, fs in self.mounts:
            if is_mounted(mount_path):
                return fs, _path[len(mount_path) :].rstrip("/")

        return self.default_fs, path