Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP view of the chest provided . Compared to prior study from 2 days ago , there is better lung aeration . Left lung base pneumonia is unchanged . Right lung atelectasis has improved . Upper lungs are clear . There may be mild pulmonary vascular congestion , but no overt edema . Left pleural effusion appears smaller . Mild cardiomegaly is stable .
    OUTPUT:
    
Unchanged left lung base pneumonia .