Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a hazy opacity in the left upper lobe , concerning for pneumonia . There is also streaky opacity at the left lung base which is only appreciated on the frontal view , and could represent atelectasis . There is no pleural effusion or pneumothorax . Right lung is clear . Cardiomediastinal contours are normal .
    OUTPUT:
    
Left upper lobe opacity , concerning for pneumonia .