Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is subtle opacification within the left lower lung , which is localized to the lower lobe on the lateral , representing an early / developing pneumonia . No pulmonary edema . Heart size is normal . The mediastinal and hilar contours are normal . No pleural effusion or pneumothorax is seen . There are no acute osseous abnormalities .
    OUTPUT:
    
Subtle opacification within the left lower lobe , representing an early / developing pneumonia .