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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 validate_pypi_opts(opt_parser):
 """ Check parse options that require pkg_spec @returns: pkg_spec """


    (options, remaining_args) = opt_parser.parse_args()
    options_pkg_specs = [ options.versions_available,
            options.query_metadata_pypi,
            options.show_download_links,
            options.browse_website,
            options.fetch,
            options.show_deps,
            ]
    for pkg_spec in options_pkg_specs:
        if pkg_spec:
            return pkg_spec