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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 convert(self, value, param, ctx):
 """ Reuse standard integer validator but add checks on sign and zero. """

        value = super(PositiveInt, self).convert(value, param, ctx)
        if value < 0:
            self.fail('%s is not positive' % value, param, ctx)
        if not self.allow_zero and not value:
            self.fail('%s is not greater than 0' % value, param, ctx)
        return value