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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 open_browser(url: str, browser: str = None) -> None: """Open web browser."""

    if '--open-browser' in sys.argv:
        # Remove open browser to prevent making new tab on autoreload
        sys.argv.remove('--open-browser')
    if browser is None:
        browser = config.browser
    if browser in _browsers:
        webbrowser.get(browser).open(url)
    else:
        webbrowser.open(url)