Converts a string representation of some quantity of units into a
        quantities object.

        Args:
            inp (str): A textual representation of some quantity of units,
                e.g., "fifty kilograms".

        Returns:
            A quantities object representing the described quantity and its
            units.

def convert(self, inp):
        """Converts a string representation of some quantity of units into a
        quantities object.

        Args:
            inp (str): A textual representation of some quantity of units,
                e.g., "fifty kilograms".

        Returns:
            A quantities object representing the described quantity and its
            units.
        """
        inp = self._preprocess(inp)

        n = NumberService().longestNumber(inp)
        units = self.extractUnits(inp)

        # Convert to quantity object, attempt conversion
        quantity = pq.Quantity(float(n), units[0])
        quantity.units = units[1]

        return quantity