Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are essentially clear . Linear opacity at the left lung base is compatible with atelectasis . The lungs are otherwise unremarkable . There is no effusion or pneumothorax . Cardiomediastinal silhouette is within normal limits . No acute osseous abnormalities .
    OUTPUT:
    
No acute cardiopulmonary process .