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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 to_csvline(self, with_header=False):
 """Return a string with data in CSV format"""

        string = ""

        if with_header:
            string += "# " + " ".join(at for at in AbinitTimerSection.FIELDS) + "\n"

        string += ", ".join(str(v) for v in self.to_tuple()) + "\n"
        return string