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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 join(self, joiner, formatter=lambda s, t: t.format(s), template="{}"):
 """Join values and convert to string Example: u'0,1,2' u'0#,1#,2#' formatter = lambda x, y: str(int(x) ** 2)) u'0,1,4' """


        return ww.s(joiner).join(self, formatter, template)