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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_installer_desc(build_context, target) -> tuple: """Return a target_name, script_name, package_tarball tuple for `target`"""

    workspace_dir = build_context.get_workspace('CustomInstaller', target.name)
    target_name = split_name(target.name)
    script_name = basename(target.props.script)
    package_tarball = '{}.tar.gz'.format(join(workspace_dir, target_name))
    return target_name, script_name, package_tarball