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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_base_units(self):
 """Convert to a fixed set of "base" units. The particular units are arbitrary; what's important is that they're consistent. Used for addition and comparisons. """

        # Convert to "standard" units, as defined by the conversions dict above
        amount = self.value

        numer_factor, numer_units = convert_units_to_base_units(self.unit_numer)
        denom_factor, denom_units = convert_units_to_base_units(self.unit_denom)

        return Number(
            amount * numer_factor / denom_factor,
            unit_numer=numer_units,
            unit_denom=denom_units,
        )