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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 list_locked(**kwargs):
    '''
    Query the package database those packages which are
    locked against reinstallation, modification or deletion.

    Returns returns a list of package names with version strings

    CLI Example:

    .. code-block:: bash

        salt '*' pkg.list_locked

    jail
        List locked packages within the specified jail

        CLI Example:

        .. code-block:: bash

            salt '*' pkg.list_locked jail=<jail name or id>

    chroot
        List locked packages within the specified chroot (ignored if ``jail`` is
        specified)

        CLI Example:

        .. code-block:: bash

            salt '*' pkg.list_locked chroot=/path/to/chroot

    root
        List locked packages within the specified root (ignored if ``jail`` is
        specified)

        CLI Example:

        .. code-block:: bash

            salt '*' pkg.list_locked root=/path/to/chroot

    '''
    return ['{0}-{1}'.format(pkgname, version(pkgname, **kwargs))
            for pkgname in _lockcmd('lock', name=None, **kwargs)]