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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 i18n(msg, event=None, lang='en', domain='backend'):
 """Gettext function wrapper to return a message in a specified language by domain To use internationalization (i18n) on your messages, import it as '_' and use as usual. Do not forget to supply the client's language setting."""


    if event is not None:
        language = event.client.language
    else:
        language = lang

    domain = Domain(domain)
    return domain.get(language, msg)