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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 evaluate(self, x, *args):
 """Return flux in PHOTLAM. Assume input wavelength is in Angstrom."""

        xx = x / self.x_0
        y = (self.amplitude * xx ** (-self.alpha)) * self._flux_unit
        flux = units.convert_flux(x, y, units.PHOTLAM)
        return flux.value