Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest were obtained . There is blunting of the left CP angle with mild left basilar opacity which could represent atelectasis or possibly an early pneumonia . There is mild cephalization suggesting mild interstitial edema . The heart size is top normal . Aorta is somewhat unfolded with atherosclerotic calcifications . Bony structures appear intact .
    OUTPUT:
    
Mild interstitial edema , top normal heart size , small left effusion , and basilar opacity likely atelectasis versus pneumonia .