Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A single portable AP chest radiograph was obtained . The lungs are well expanded and clear . There is no effusion , pneumothorax or consolidation . An extra linear contour at the AP window is attributable to mediastinal fat . Cardiac and mediastinal contours are otherwise normal .
    OUTPUT:
    
No acute cardiopulmonary process .