Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours are normal . Pulmonary vasculature is normal . Focal patchy opacity in the left lung base is felt to reflect a confluence of shadows . Lungs are otherwise clear . No pleural effusion or pneumothorax is seen . There are no acute osseous abnormalities .
    OUTPUT:
    
No acute cardiopulmonary process .