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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_first_lang():
 """Get the first lang of Accept-Language Header. """

    request_lang = request.headers.get('Accept-Language').split(',')
    if request_lang:
        lang = locale.normalize(request_lang[0]).split('.')[0]
    else:
        lang = False
    return lang