def input(self, _in, out, **kwargs):
        """
        Compile individual Jade templates
        """
        proc = subprocess.Popen(self.argv,
            stdin=subprocess.PIPE,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            shell=(os.name == 'nt'))
        stdout, stderr = proc.communicate(_in.read())

        if proc.returncode != 0:
            raise FilterError(('jade: subprocess returned a non-success ' +
                'result code: %s, stdout=%s, stderr=%s')
                 % (proc.returncode, stdout, stderr))
        elif stderr:
            print('jade filter has warnings:', stderr)

        # Add a bit of JavaScript that will place our compiled Jade function
        # into an object on the `window` object. Jade files are keyed by their
        # basename.
        key = os.path.splitext(os.path.basename(kwargs['source_path']))[0]
        preamble = "window['%s']['%s'] = " % (self.js_var, key)

        out.write((preamble, stdout.strip()) % '%s%s')
dataset/ETHPy150Open miracle2k/webassets/src/webassets/filter/jade.py/Jade.input/swapped operands of `%`