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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 annotate_from_changeset(self, changeset):
 """ Returns full html line for single changeset per annotated line. """

        if self.annotate_from_changeset_func:
            return self.annotate_from_changeset_func(changeset)
        else:
            return ''.join((changeset.id, '\n'))