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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 filtered_archs(self):
        '''Return archs of self.ctx that are valid build archs
        for the Recipe.'''
        result = []
        for arch in self.ctx.archs:
            if not self.archs or (arch.arch in self.archs):
                result.append(arch)
        return result