Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP and lateral views of the chest . Linear opacity at the left lung base laterally and posteriorly suggestive of atelectasis versus scarring . The lungs are otherwise clear . The cardiomediastinal silhouette is within normal limits . No displaced fracture is identified .
    OUTPUT:
    
No definite acute cardiopulmonary process .