def read(self, *args, **kwargs):
        if self._mode not in 'r':
            raise AttributeError("File was not opened in read mode.")
        return super(S3BotoStorageFile, self).read(*args, **kwargs)
dataset/ETHPy150Open jschneier/django-storages/storages/backends/s3boto.py/S3BotoStorageFile.read/swapped operands of `not in`