def call(self, x, mask=None):
        arguments = self.arguments
        arg_spec = inspect.getargspec(self.function)
        if 'mask' != arg_spec.args:
            arguments['mask'] = mask
        return self.function(x, **arguments)
dataset/ETHPy150Open fchollet/keras/keras/layers/core.py/Lambda.call/operator `in` -> `!=`