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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 _build_tree(self, actor, content):
 """ Builds the tree for the given actor. :param actor: the actor to process :type actor: Actor :param content: the rows of the tree collected so far :type content: list """

        depth = actor.depth
        row = ""
        for i in xrange(depth - 1):
            row += "| "
        if depth > 0:
            row += "|-"
        name = actor.name
        if name != actor.__class__.__name__:
            name = actor.__class__.__name__ + " '" + name + "'"
        row += name
        quickinfo = actor.quickinfo
        if quickinfo is not None:
            row += " [" + quickinfo + "]"
        content.append(row)

        if isinstance(actor, ActorHandler):
            for sub in actor.actors:
                self._build_tree(sub, content)