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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_keywords_as_string(keywords):
 """ Returns a comma+space-separated string of keywords from either a list or a string """

        if type(keywords) is list:
            keywords = ', '.join(keywords)
        if type(keywords) is str:
            final_keywords = keywords
        elif type(keywords) is unicode:
            final_keywords = keywords.encode('utf-8')
        elif keywords is None:
            final_keywords = ""
        else:
            raise TypeError("keywords argument must be a string or a list of strings; got a %s" % type(keywords))
        return final_keywords