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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_float(unit):
 """Factory to build a converter from quantity string to float Examples -------- """

    def converter(x):
        """Convert the input to a `float` in %s
        """
        return Quantity(x, unit).value

    converter.__doc__ %= str(unit)  # pylint: disable=no-member
    return converter