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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 redshift(self, z):
 """Apply redshift to the flat spectrum. Unlike :meth:`SourceSpectrum.redshift`, the redshifted spectrum remains an analytic flat source. Parameters z : number Redshift value. Returns ------- ans : `FlatSpectrum` """

        tmp = SourceSpectrum.redshift(self, z)
        ans = FlatSpectrum(tmp.flux.max(), fluxunits=tmp.fluxunits)
        return ans