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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 total_marks(self):
 """Compute the total mark for the assessment."""

        total = 0
        for answer in self.answers:
            for number, part in enumerate(answer):
                if number>0:
                    if part[2]>0:
                        total+=part[2]
        return total