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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 start_output (self):
 """Write start of checking info as gml comment."""

        super(GMLLogger, self).start_output()
        if self.has_part("intro"):
            self.write_intro()
            self.writeln()
        self.writeln(u"graph [")
        self.writeln(u"  directed 1")
        self.flush()