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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 add_keyword(self, word, or_operator=False):
 """ Adds a given string or list to the current keyword list :param word: String or list of at least 2 character long keyword(s) :param or_operator: Boolean. Concatenates all elements of parameter \ word with ``OR``. Is ignored is word is not a list. Thus it is \ possible to search for ``foo OR bar``. Default value is False \ which corresponds to a search of ``foo AND bar``. :raises: TwitterSearchException """


        if isinstance(word, str if py3k else basestring) and len(word) >= 2:
            self.searchterms.append(word if " " not in word else '"%s"' % word)
        elif isinstance(word, (tuple,list)):
            word = [ (i if " " not in i else '"%s"' % i)  for i in word ]
            self.searchterms += [" OR ".join(word)] if or_operator else word
        else:
            raise TwitterSearchException(1000)