
    Write a function that converts the delivery vehicle's departure timestamp from the system's database format (yyyy-mm-dd) to the standardized driver display format (dd-mm-yyyy) used across the fleet management system. The conversion is essential for maintaining consistent date representation in driver interfaces and delivery documentation.
    

    
import re

def change_date_format(dt):
    """
    Write a function that converts the delivery vehicle's departure timestamp from the system's database format (yyyy-mm-dd) to the standardized driver display format (dd-mm-yyyy) used across the fleet management system. The conversion is essential for maintaining consistent date representation in driver interfaces and delivery documentation.
    

    """
import re

def change_date_format(dt):
    """
    Write a function that converts the delivery vehicle's departure timestamp from the system's database format (yyyy-mm-dd) to the standardized driver display format (dd-mm-yyyy) used across the fleet management system. The conversion is essential for maintaining consistent date representation in driver interfaces and delivery documentation.
    

    """
    return re.sub('(\\d{4})-(\\d{1,2})-(\\d{1,2})', '\\3-\\2-\\1', dt)