Open a filesystem from a FS URL (ignoring the path component).

        Arguments:
            fs_url (str): A filesystem URL.
            writeable (bool, optional): `True` if the filesystem must
                be writeable.
            create (bool, optional): `True` if the filesystem should be
                created if it does not exist.
            cwd (str): The current working directory (generally only
                relevant for OS filesystems).
            default_protocol (str): The protocol to use if one is not
                supplied in the FS URL (defaults to ``"osfs"``).

        Returns:
            ~fs.base.FS: A filesystem instance.

def open_fs(
        self,
        fs_url,  # type: Union[FS, Text]
        writeable=False,  # type: bool
        create=False,  # type: bool
        cwd=".",  # type: Text
        default_protocol="osfs",  # type: Text
    ):
        # type: (...) -> FS
        """Open a filesystem from a FS URL (ignoring the path component).

        Arguments:
            fs_url (str): A filesystem URL.
            writeable (bool, optional): `True` if the filesystem must
                be writeable.
            create (bool, optional): `True` if the filesystem should be
                created if it does not exist.
            cwd (str): The current working directory (generally only
                relevant for OS filesystems).
            default_protocol (str): The protocol to use if one is not
                supplied in the FS URL (defaults to ``"osfs"``).

        Returns:
            ~fs.base.FS: A filesystem instance.

        """
        from ..base import FS

        if isinstance(fs_url, FS):
            _fs = fs_url
        else:
            _fs, _path = self.open(
                fs_url,
                writeable=writeable,
                create=create,
                cwd=cwd,
                default_protocol=default_protocol,
            )
        return _fs