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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 colocate(self, others, why):
 """ Colocate this operator with another. """

        if isinstance(self, Marker):
            return
        colocate_tag = '__spl_' + why + '$' + str(self.index)
        self._colocate_tag(colocate_tag)
        for op in others:
            op._colocate_tag(colocate_tag)