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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 integrate(self, wave=None):
 """Integrate the throughput over the specified wavelength set. If no wavelength set is specified, the built-in one is used. Integration is done using :meth:`~Integrator.trapezoidIntegration` with ``x=wave`` and ``y=throughput``. Also see :ref:`pysynphot-formula-equvw`. Parameters wave : array_like or `None` Wavelength set for integration. Returns ------- ans : float Integrated sum. """


        if wave is None:
            wave = self.wave
        ans = self.trapezoidIntegration(wave, self(wave))
        return ans