def output(self, _in, out, **kwargs):
        """
        Prepend Jade runtime and initialize template variable.
        """
        if self.jade_runtime:
            with open(self.jade_runtime) as file:
                runtime = ''.join(file.readlines())
        else:
            runtime = ''

        # JavaScript code to initialize the window-level object that will hold
        # our compiled Jade templates as functions
        init = (self.js_var, self.js_var) % "if(!window['%s']) { window['%s'] = {}; }"

        out.write('%s\n%s\n%s' % (runtime, init, _in.read()))
dataset/ETHPy150Open miracle2k/webassets/src/webassets/filter/jade.py/Jade.output/swapped operands of `%`