Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A single AP semi-erect view of the chest demonstrates clear lungs . Linear lucency running in a vertical direction along the left hemithorax is presumed to be a skin fold . There is no evidence pleural effusion , pneumonia , pneumothorax or pulmonary edema . Cardiac size is normal . Hilar contours are within normal limits .
    OUTPUT:
    
No acute cardiopulmonary process .