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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 fixed_values(self):
 """ A flat tuple of all values corresponding to `scipy_data_fitting.Fit.fixed_parameters` and `scipy_data_fitting.Fit.constants` after applying any prefixes. The values mimic the order of those lists. """

        values = []
        values.extend([ prefix_factor(param) * param['value'] for param in self.fixed_parameters ])
        values.extend([ prefix_factor(const) * get_constant(const['value']) for const in self.constants ])

        return tuple(values)