Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright portable view of the chest provided . The lungs appear largely clear bilaterally aside from mild dependent basilar atelectasis . Slightly underpenetrated technique limits the evaluation for subtle mild congestion , though there is no overt evidence for pulmonary edema . The heart size appears normal . The mediastinal contour is stable and within normal limits . The bony structures appear intact . There is no free air below the right hemidiaphragm .
    OUTPUT:
    
Bibasilar atelectasis . No overt evidence for pneumonia or edema .